I'll try to address both of these points, but forgive me if they aren't too helpful.
Your issue is a fair one, and my only response is that I assume that those who sign-up away from home are in a the minority. Of course the statistics will be slightly skewed, but I still believe that even when taking this into account, the winning city will have won fairly.
To be able to answer your question, I'd have to give away a bit more about the concept than I'm willing to at this point, so I hope this explanation helps:
Advanced metrics don't work. Long, boring resumes don't work. Nothing can be more helpful than just getting into coffee shop with someone and having a chat about ideas that really excite you. GetFounder is about getting entrepreneurs and technical people who share the same vision into that situation.
We have one or two 'profile' fields that overlap with those found on sites like StartupWithMe, but I believe that GetFounder's true potential is found in its simplicity.
I don't think you'll have seen matchmaking like this. I really cant wait to show it to you!