We generally never hire anyone we haven't seen before, unless there's overwhelming evidence that they'll kick ass. For example, we hired Pratik Naik from London

We generally never hire anyone we haven't seen before, unless there's overwhelming evidence that they'll kick ass. For example, we hired Pratik Naik from London and it took more than a year before he met anyone else in the office (couldn't get a visa). For everyone else, we fly them into the office to determine if they'll be a good social fit. If so, they're hired and fly back home to get work done. Works great!