I would personally go for the SP Vibe. The main reason being it can run on both Co2 and Air. As well as the fact that it can be upgraded to a large degree. For example, I have a Vibe with.......
Clamping feedneck
Sly grips
L7 tech bolt
Custom Parts barrel
Blackheart board
(And soon to change reg)
And can say without a doubt its a great marker. Its not the lightest, fast, indestructable Etc marker, but it will get you through most competitions/games without any major problems. Plus the body can be sprayed quite easily if you want to make its dark shell a bit more Vibrant. And for the price its not the end of the world if you break it.
Oh and a few more points. I've try and tested many other markers and not many are as easy as this to clean, you do have the Tippmans and a few others but in terms of cleaning time this marker is quick. Anyway as soon as mine is back from LIPS I'll post some picture to give you a clue of how nice these Vibes can look.
Now I know you can argue that with the extra upgrade cash you could get something better, but its nice to have something less common than your typical popular marker. (I know way to many people with ego's and ions, so I like to see something that leaves the observer curious, wondering what it is so to speak).