Hyper 3 is good replacement for the stock reg if you want to blow money. Same principle with the rubber. Feedneck seems like it'd be a good investment, but all the aftermarket ones are ugly and don't match the outside diameter that the stock one has (it just makes it look janky IMO). I'm glad I made the investment in my Vibe.
I shot my Vibe last week (or a friend did rather) but, I chronographed it for him. It shot 283, 283, 285. I have a freak barrel now. So my build is COMPLETE! I'll have to post pics tomorrow or something.
But if I had to buy it new I would get:
-GOG Envy with Blackheart Board
-Nice On/Off (I love Bob Long and NDZ ones that come out the front)
-Techt L7 Bolt or DW Hollowpoint Bolt
-Vibe Reg cover (and make it fit)
-Cheapest Kind of Spring/Ball and Plunger Detents you can find
That's how mine is and it shoots great and I love it for being such a reliable, accurate and great feeling marker. And I've owned plenty of high-end markers (although the high-end ones do FEEL better in the hands, because I have small hands and the grip frames are smaller on high-end markers).