There's always been something fishy about 37signals that I can't put my finger on. I respect what they've done but know that I definitely don't want to run a company like they do. Firstly, they charge for everything they possible can. This is not necessarily bad in and of itself but at some point they stop feeling like a product company. First and foremost they're a brand company. I can't help but think they'll sacrifice quality in any other area if it helps their brand out. That's probably not entirely fair, but it's the picture they've painted.
I just want to build cool stuff. I know brand is important but it seems silly to me to try and make a career out of blathering about how awesomely I build cool stuff and how much I just get it where so many others don't.