I'm not sure what she means by bottom loading,unless she means Drop in,vs loaded in from the side.But yes there are tons of machines with drop in bobbins.

Here's a link you may want to read before you go shopping,it has lots of good information.

http://www.quilt.com/FAQS/SewMachinePurchaseFAQ.html

Then you can also google sewing machines with drop in bobbins and you'll see many of them.
Good luck with your search and classes.Come back and let us know how you are doing,and welcome to the forum
Kathi

I can't imagine why she recommends one over the other or what she means either. I have a lot of machines, both home and industrials. Most have the side load (at the bottom) and I have a Singer with the drop in (but also at the bottom).
There's probably more to choose from with the side load, but I can't see any actual difference in the sewing between the two, and I've been sewing forever.
I would just buy the machine I liked and not worry about it.

I didn't know what a "bottom loading" bobbin was either so I googled it. The following is extracted from an article on the Bernina and explains why they choose to use this feature in their machines. Pay attention to the last line or so. I would say that if you are going to be doing a lot of quilting or machine embroidering then you might want to consider it but otherwise not.

"An example of this "quality without compromise" in Bernina sewing machines is in their approach to bobbin design. In a mid to top level machine from any of the major sewing machine brands, you would expect to see a top loading bobbin. However, Bernina sewing machines retain a bottom loading bobbin design. This is done on the basis that a bottom loading bobbin design provides a better-quality system giving better stitch quality, longer life, greater reliability, which is also just the thing for embroidery and quilting, while at the same time accepting that a bottom loading bobbin design is likely to result in a machine which is slower and noisier."

I have a Bernina and two Vikings. Both Vikings are have different bobbins. The only difference I see is the top bobbin (sits horizontally under pressure foot/feed dogs) holds less thread then the vertical bobbin. The only problem I have is the amounts of bobbins I have for the vertical bobbin (over 20)for I do alot of garments sewing and also teach sewing.

I have never before heard the term "bottom loading". I like to refer to the orientation of the sewing hook, as machines with drop-in bobbins have hooks that move in a horizontal plane, while front-loaders with removable bobbin cases (like Bernina) have vertical hooks. I really like vertical hooks for free-motion embroidery and quilting, but I am wayyyyyy too cheap to ever pop for a Bernina. With a vertical hook, the thread loop is drawn around the bobbin in a single vertical plane, while with a horizontal hook, the thread has to be dragged sideways to get around the bobbin. This deflection of the thread path can be more problematic with FM work, as your hands have to replace the action of the feed dogs to make good stitches. Also, unusual threads which some of us like to use for decorative effects sometimes have difficulties negotiating the 3-D path and require constant tension tweaking.

My current favourite FM machine is a 1915 Singer 115. There are many vintage Singers with vertical hooks that are good FM quilters (for example, all class 15s), but I doubt any current ones do. I'm not very familiar with current machines, except that most of them have horizontal hooks, except for maybe some of the large format quilting machines.