This topic has come up a few times here. This what I found when I googled undermount sink in laminate counter. It is from bobvila.com

Sink Limitations
A drop-in or self-rimming sink is typically used with laminate kitchen counters. The raw edge around the sink must be sealed properly so water can't penetrate between the sink and the countertop. As long as the edge is sealed, problems like delamination are unlikely.

If water problems occur, they typically affect the substrateÂthe particle or medium-density fiber boardÂto which the laminate is bonded. When penetrated by water, the substrate actually swells and deteriorates, leaving unsightly warping, bumps, and gaps.

Undermount sinks are typically discouraged with laminate counters because it is so difficult to guard against water penetration. If you are determined to use an undermount sink, consider Counter-Seal's undermount sink system or work with a fabricator to make an impenetrable seam between sink and counter.

Here is a link that might be useful: Counter- Seal

I got a Karran undermounted sink with new laminate counters at my lake place earlier this year. I'm lovin' it so far. I did get a sink with a faucet deck so if I ended up having some kind of problems and had to get a different sink I could just swap it out and not have to deal with faucet holes in my laminate. Plus something about the faucet going through the laminate just made me think more potential complications. The contractor who did the work said his counter guy had done quite a few of these with good results and felt it was a "good system".

I do think the sink itself is a bit more prone to staining than the Corian sink I have at home and takes a little more effort to clean than my Corian sink. That kind of thing doesn't bother me but I know some people hate it so I wanted to mention it.

The other thing I do sometimes wonder about is chipping the edge of the laminate around the sink. You know how those edges on a laminate counter seem to chip. I am careful not to bang things against the edge. Overall though I really like it. So nice to be able to just wipe things into the sink plus I have more counterspace without the big edge I used to have with my cast iron sink. Here's a picture.

{{!gwi}}