If you're in the market for Kohler fixtures, you can see what seems like their entire catalog by going to Keller Supply in Redmond. While the Keller Supply website indicates that they (their warehouse) carry dozens of brands, the showroom is almost entirely dominated by Kohler tubs, sinks, faucets, showers, and toilets. There are a few other designer brands that you don't see at the big box places like Lowe's and Home Depot, too, but they comprise maybe 10-20% of the showroom floor.
The store is laid out pretty well, with sinks mostly in one area and faucets and showerheads in another. Their bathroom faucets are actually hooked up to the plumbing so you can judge them based on function as well as form. I also really liked the pull-out drawers that allow them to maximize display space for sinks, but I didn't like the fact that there were no price tags, not even price tags with MSRPs. They had finish samples on kiosks here and there, but for the most part, display items were in standard white.
My husband and I would have liked to talk to someone, but customer service in the showroom is available only by appointment. We didn't know this ahead of time. It's a good thing they have a sign in the showroom telling you as much because I would have been really offended that they acknowledged us with nary a glance or a nod. This seemed like an unnecessarily snooty way of conducting business and definitely turned me off.
After browsing the showroom, we stopped in the warehouse to see if they had a sample product in the back that they didn't have in the showroom. While the guy at the desk was reluctant to go check, he ultimately did. This helped to sort of redeem the place in my mind. That said, they still carry lots of brands and contractors and builders apparently like to use them, so if you see something you want on their website, you can order it online or through your contractor instead of wasting a trip to the showroom.