I've used Windowsblinds for years now. I like it better. Even now, there are very few good StyleXP themes. They are all pretty much recolorized versions of Luna, with one or two adjustments. There are thousands of Windowsblinds themes out there, and I'd say at least 250 (of the ones I've found, at least) are good. In the end, that's what counts. There's no use for a theme switcher if there are no good themes for it out there. Windowsblinds 2.x was buggy, slow, and wouldn't run well on anything less than a 1GHz machine. That's all changed with 3.x. I got it to run perfectly on a 500MHz Celeron with 96MB of SDRAM. It runs equally as well as StyleXP on my current Athlon XP 1800 with 512MB DDR box. I notice no difference at all in resource use. Also, no bugs. It even works well with programs that don't skin well such as Photoshop 6 and Trillian (Pro and otherwise). Windowsblinds 2.x and StyleXP would completely fudge up both programs.
I don't know what people are complaining about with regards to Windowsblind's obtrusiveness. It puts one icon in the systray, but you can configure to not display it. The actual configuration is via the Display Properties panel. Works well, and a logical choice.
For the freedom to express myself in my own way without fear of being censored or banned.