Axes have been going for £200-230 that ive seen lately (which is great!) Cant really comment on proto's the only guy that has one at the site i go to spends more time fixing it than he does playing... Getting stuff new is all well and good but then you have to break in the marker etc etc i had problem after problem with a brand new phenom whereas my mate who got his second hand had no problems. I just sold the damn thing and got a used Ego, never looked back.
People on my team have axes, the only problem ive seen is the stock barrel isnt the best but other than that it fires beautifully and none of them have ever had any problems with it at all, really easy to maintain after a days play too.