It really depends on the "trust" the two people have. Cause it's hard to stick to a commitment wherein 你 don't see each other in real time, and 你 can't even know what he/she is doing.
For my personal opinion, it doesn't work 100% but if 你 believe in it, it's all worthed.
It CAN work if both people are really committed, but it's hard. I'm in the process of having one right now. It's also much easier if 你 use a webcam thing like Skype and also have phone calls, and of course visits in person whenever 你 can.
Long distance relationships are cute in a way. But it's a waste of time if 你 can never see 你 bf/gf :( So I prefer having a boyfriend that I can meet whenever I want