I've done trades for camera gear and video game stuff. I've even done 3 ways trades (this saves on shipping for all parties). Obviously, when it comes to money, whoever is sending money, sends first and than seller ships. When it comes to trades, you have 2 options. Person with lowest amount of feedback or reference, ships first. Or, you both ship at the same time with tracking and insurance and provide the information to each other.
The more reference the better. It could be from POTN, FM or eBay. Because someone could be new to the site and hasn't done much transactions but is a long time seller/buyer elsewhere. We all started somewhere. On FM, I have 27 feedbacks. On POTN, I have about 8. Videogame sites, I have a few hundred and on eBay, I have over 1270.
But if someone has minimal feedbacks or references from other sites and still insists that you send first, I would be hesitant. Granted, they don't want to get ripped off but they're at the bottom of the totem pole and need to work their way up.