I've been trying to play reflex for a while now. single player is OK. Multiplayer you usually can't get into any games, and invite friends never works. Not much fun if I can't play with my buddies. Feel like I wasted the money on the game. I'm sure it has to do with port forwarding through the router, but for some reason THQ cant' seem to be bothered with listing the ports the game needs opened.
Anyway, unless you want to remove your router and plug your PC directly into the modem so you can play online, don't bother with this one. At least not until they release a patch or some info on ports to forward.