Another option is to import the stems into Reaper and change the playback rate of each media item / track and export new stems. It uses Elastique Pro and the playrate feature works great. Audition the speed change in realtime and then render the individual stems at the new rate.
It will render all of the stems in one pass at the same time at the new rate. Then import them back into Pro Tools or whatever daw you're working in and get back to work. I use it with Cubase for that kind of thing.
Here's a sample of the quality:
Original: http://theaudiocave.com/ewf1.mp3 10% faster: http://theaudiocave.com/ewf2.mp3
It's as easy as drag selecting all the audio in the project, changing the playrate (1.1000 = 110% etc) and render all tracks to stems. Pitching works just as well.
Original pitched up 2 semitones: http://theaudiocave.com/ewf3.mp3
Probably cheaper and as good or better quality than most any plug that can do that. Cubase has Elastique Pro as well but you have to render them one at a time, realtime preview is very poor, and Reaper's final quality is a touch better. Handy tool.