I had a good experience with my group, everybody worked together to create something we all liked, and it can be fun working with different people. Thus, I enjoyed our project.
However, generally speaking now, I honestly don't always see it positively when teachers require us to work with different classmates, because, despite the fact that that gives you opportunities to learn from distinct people with new ideas, I still believe that your level of comfort with collaborators has a great impact on your work. I, for instance, am a very timid person and take time to feel comfortable enough to voice my opinions, therefore, I tend to get quiet and not to be as collaborative as I would in another situation. There is also the personality issue - some personalities just don't go together honestly.
Maybe it is something I must learn to do (getting over being shy around new people in order to be more productive), but I also wonder how important it is to make students comfortable so they can work better. Perhaps, it is more productive to let students choose their coworkers when it comes to work that is going to be graded, and encourage them to collaborate with different people in small projects that don't have a significant impact on their grade.
