Nothing NEEDS upgrading. It runs at a low pressure, but the reg is designed for either high or low pressure input. So any quality regged tank will work just fine on it. The PE tanks are high pressure, so no issues running a HP tank. They're not as nice as the newer Egos, but they still shoot just fine, and can keep up with anything out if you don't mind the few extra ounces of weight.
Milling & weight obviously. I'm not certain if they changed anything else. The 07 came with zick, the 08 with cure2 bolt, the 09 with a new noid. I can't remember what the internal change from 05-06 was though, or even if there WAS an internal change.
06 came with QEVs, 05s didn't have them at all. The cure bolt originally came out for the 06 yeah. Then hte cure2 for the 07, only difference is the cupped face which really does nothing but gives the gun a chance for roll back.
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06 came with QEVs, 05s didn't have them at all. The cure bolt originally came out for the 06 yeah. Then hte cure2 for the 07, only difference is the cupped face which really does nothing but gives the gun a chance for roll back.
I've had every other person tell me something different on that. I've had a dozen people say 05's DO have QEV's stock, dozen say they don't. I could have sworn when the 06 was released that I remember the 05 NOT having them too, but since I've never owned one, I don't totally trust my memory of that long ago. Of course, my buddy SHOOTS an Ego5, yet I've never thought to ask him.