I've always liked the looks of the ones that are built into the lowest shelf of the uppers.

I've never had one down low in the island but a friend does and she complains about having to bend over all the time to reach in.

In our recently completed kitchen we put a microwave drawer in the island.
It is right in the heart of our main work zone, one steps from the sink,
one step from my main prep area and range.
We are finding it a great location so far, especially since
I use the microwave a fair amount when cooking
(melting butter, defrosting, etc.)
In our old kitchen the microwave was about 20 steps away on a shelf in the pantry.
So I am really loving the new convenient location.
When planning the kitchen I was at first a bit skeptical about the benefits of the micro drawer, especially given the cost.
I can report that at 5 feet 8 inches I have no problem using it;
I do not feel like I'm hurting my back stooping, and I have no problem it cleaning it.
It holds a 13 by 9 inch pan comfortably.
While not for everyone, a microwave drawer in the island is certainly an option to consider.

We put ours on a shelf 13 inches above the counter and just love it. It is a bit lower than an OTR model yet is not taking up counter space or over the cooking area. Our young sons (8 & 9.5) can reach it easily enough. I love how it does not accumulate dh's odds and ends on top like our old one on the counter did. We have it between the sink and the fridge and love how it is not in the way of anything. We don't have uppers on that wall, but someone could put a short one above it if they needed to....
Our toaster is on the back of the counter below it, so both are away from the cooking zone on the island and out of the cook's way. I can use it easily, but so can others without bothering my prep spaces or stove. Putting it up a little high also gave it a landing zone below it.

We put a MW drawer in our island....it has been no problem at all. No one, not even my 6'4" dh has complained about bending over...actually, it doesn't seem to make anyone bend over. We really love it.

Another drawer micro here. We also wanted to move the micro and thought we could modify an upper to accomplish that, but we found that there was no good place for it. I didn't ant an undercounter that I had to bend and reach into like an undercounter cave. The drawer solved our layout issues, but it has also been a great micro. I have one mug, my tallest one and my largest mixing bowl, but the tallest mug is the one I steam milk in so I don't have to use a frothing pitcher and then pour into a cup and I generally don't nuke my coffee after that. The only time I used my large mixing bowl in the old micro was to soften butter which I can easily do in a smaller bowl or simply put it in the KA and turn it on to soften it quickly without melting -- so I haven't really missed a taller micro but I do like the size of the drawer for casseroles and such. It definitely fits a larger pan than the old one.

We range from 5'8" to 6"3 and my brother is 6'7" and no one has complained about the height. In fact, it seems easier to lift up than up and out and there is the plus of not having to remove the dish at all to stir or check. The drawer is a change, but it's a good one for us.

Just put a microwave on the floor or a couple of feet above it. Use it that way for a few weeks and then decide. I couldn't stand it. I knew that a microwave below counter height would drive me nuts! I think it looks cool, but it is not practical.
I have had microwaves installed above my range, on my counter, and my experimental floor location and I like one on the counter the best.

Another fan here of a micro shelf in or under the upper cabinets. It's a comfortable, safe height, and I can use a cheapie model that won't cause me undue angst or inconvenience if/when it reaches its design life limit before I think it should.

We have a MW drawer and we're all very happy with it. We range in height from 5'10" (me - the shortest) to my DS at 6'6". None of us has had an issue with using it. No bending over to access food or to read/use controls. The inside is actually quite roomy...especially the newer ones (they're now tall enough for those tall cups of coffee). All my casserole dishes (round & rectangular and shallow & deep) fit in it without problems. The only thing that does not fit is the glass cover of my largest round casserole dish (b/c of the glass knob)...so I just use wax paper when I use that particular dish (or turn the cover upside down if the "food height" allows)

Here are some recent (and one not so recent) threads that discuss MW drawers:

Thread (2010 & probably the most useful): Microwave Drawer Pros and Cons?

Thread: Who has a microwave drawer?

Thread: Sharp drawer microwave - do thy fit a 10' dinner plate?

Thread: undercounter microwaves - pics please?

We have a microwave drawer in our island am I'm so glad we put it there! If we had put it where it was originally going to go (in a built in cabinet between the end upper cabinet and counter) it would have closed off the end of our cabinet and not had an open flow. Now it looks great in the island and is out of the way. I have enjoyed using the drawer and it is easy to use.

Couldn't budget for the MW drawer, so I have a freestanding MW in my island with the trim kit. Yes, it is a bit of a pain, and I certaining can't use the clock on it without bending down a lot (we don't even set it actually). But for us it was worth it to get it off the counter.

The drawer would allow you better access to the controls, but at a $1000 premium we're (relatively!) young and healthy, so stooping down isn't a big deal. And the kids love it, since it's at their height.

One thing about our new MW is that it's pretty much one touch and go... lots of sensor cooking so not much reason to have to bend down to monitor the food inside.
People are going to get tired of pictures of my MW, but here it is again!:

We got our sharp 30" micro drawer for 797.00 on amazon.

"...Couldn't budget for the MW drawer, so I have a freestanding MW in my island with the trim kit...."

When we priced out MWs, the drawer cost the same as a MW + trim kit.

Our micro is just a regular old countertop model which we put in a cubby in the island. We are all tall. It doesn't bother anyone to bend over BUT we aren't heavy users, either. DH cooked popcorn for FIVE MINUTES, so we've already had to replace it once. I was glad it was a quick $100 changeout.

People with MW drawers seem to love them. Depends on your budget, space, and usage habits.

Co-co, I'm not tired of pictures of your MW because this is the first time I've seen it, and I'm glad to have done so. While we're at it I love the green on your walls, and I see you chose the same knob arrangement on your tall cupboards as we did on our pantry. Our knobs are actually in the middle of the style vs yours on the outer edges, but same idea. I've been pleased with that arrangement in use.

Co-co and Shanghai -- always love feasting my eyes on your kitchens!

The Canadian pricing limitation again... here the Sharp MW drawer retails for ~$1250 with taxes, whereas I bought my Panasonic + trim kit for @suzannesl: the colour is BM Stanley Park, but I think it's a Canuck colour. I'm iffy on it... I really love the colour, but sometimes think it makes my space a little too cool, especially when I see such nice warm looking kitchens like shanghai's above. Maybe I just need a better camera LOL!

Thanks to all for the feedback. We decided to go with the MW drawer. Because it's part of a four piece appliance package, we were able to get it for $500 so I thought worth the cost.