That sucks bro....sorry to hear your having all those issues. I am having some newb issues with Phoenix as well. I notice my helis "jump", for lack of a better term, at spoolup and at speed when I am doing fast circuits. i.e. it sounds like the motor cuts out for a split second. More annoying than anything.
I have RF 7 as well. I got the one that comes with the proprietary transmitter/controller so so my girlfriend and I can fly together in multiplayer mode. I just plug the DX5 into the back of the RF controller. I was told that you had to have two Phoenix USB cables and two computers for two to fly with Phoenix and it only worked over the internet or LAN. So it was cheaper to just purchase RF7 when she wanted to start flying together.
Personally, I like how the helis fly on Pheonix. It seems more real to life. Again, this may be my inexperience with RF.