I also use the Lamm M2.1s with Revel Studios (in fact, I might have to take some of the blame for Kurt_tank having his...) and agree with everything he said... except for the part about Radiohead. They're one of my favorites. If you're looking for exaggerated bass slam, the Lamms aren't the amp for you. If you're looking for the bass to be natural and realistic, you're on the right track with the Lamms. One thing I've found is that the Lamms are very sensative to tweaks, especially power cords. I'm still using the stock ones (blech) but Shunyata Pythons are in my near future. I have had a chance to demo them in my own system, and the improvements they made were stunning... from bass to treble.
I can't imagine the Lamms being lean in any circumstances. They're not overly colored, but they are on the warm, rich side of neutral. Any leanness in a system using Lamm amps would have to be blamed on something else. From what I've heard of Wilson, I think Lamm is quite possibly the perfect match.
I won't ever claim that any component is the absolute best or the absolute last I'll own (I'm too young to expect anything to last the rest of my life) but I will say that every other thing I own currently is ahead of the Lamms in my upgrade path... this includes the rest of my components, my furniture, my home, my car... you get the picture.