I just bought the 24 dollar logitech usb controller (forget the name, it's the blue cheaper version of what you're talking about). I hate to admit this, because generally speaking everything I have ever owned from Logitech (except my driving force pro) has been complete garbage. Their keyboards are junk and overpriced, their mice barring the g400 have awful sensors and terrible longevity, their headsets break religiously within 12 months. Overall the company has just evolved into complete garbage as they stick more and more "gaming" monikers on everything.
With all of that said, the cheapo 24 dollar controller is actually very good. I'd say skip the 35 dollar rumblestick crap and just get that. The Dpad is nice in street fighter 4 (shouriyuken moves are easily executed, dunno about dash characters) and it's good in Sonic Generations. I begrudgingly admit the controller is suitably decent for its price.
The xbox controller is horrendous for 1 simple reason: it has the worst D-pad in the history of video game controllers. It literally makes the atari jaguar controller look svelt and accurate. Since you want a controller for some PC gaming (emulators, classic games such as the new sonic etc) you are probably interested primarily in a D pad over stick. I have to tell you that Xbox 360 controller tried to copy what the Dreamcast did, and failed on every step of the way.