They have a dual purpose (undermount or top mount) style and strickly undermount. It's a little confusing, but it most of the sites will listing the top mount as a "dual".

We've got a dual-purpose one that's installed as drop-in (for now).

Here is a link that might be useful: pics here

pbrisjar my question is lets say you decided to use it as undermount can you leave the faucet deck area exposed also, or does the faucet need to sit on the countertop material. I am using wood countertop therefore pooling water around the faucet is a big concern for me. BUT, I think the faucet lever might hit the counter material behind it if I do this. since the wood counter are true 1.5" thick.

How come you are using as a drop in? Can you just change it easily down the road? Is the cut out size the same?

Going drop-in was one of our mistakes. Our concern (having just dealt with a rusted out cast-iron/enameled sink installed under ceramic tiles) was that in order to replace the sink, we'd have to destroy the countertop. We didn't know about the new install methods with clips, etc.

The cut-out is not the same and when we talked to our granite installer about it, they said it couldn't be changed without removing the granite and bringing it back to the shop if at all. Eventually we'll do some more research and calling around to see if we can change this but for now we have other concerns. Hubby believes taht we can do a flush-mount (where the deck will be even with the granite) but we'll have to find a granite person to modify the cut-out.

I'm not quite sure how it's installed now. I don't think it's on much (if any) of the granite as we just last week added a hole for our (new!) R/O water faucet.