agreed with Hrun... I'd probably forget to charge my 305 if it weren't for it charging whilst docked to the computer!
I've heard good things about the Suunto offerings, and they're supposed to be a cracking bit of kit - but I've never experienced one myself.
As for Garmin 405 Vs 305 - I'd say the 305 had been nearing the peaks of what could be done in terms of functionality with a GPS watch system, the 405 basically does the same thing but is more compact with a few minor revisions (such as the wireless).
I'd say the 205 & 305 has the better (bigger) display, but the 405 certainly has the 'latest model' attraction about it

Whatever you decide I'm sure you won't be dissappointed!