if your looking to all have the same marker, then the ion would be the way to go, yes, however, if you dont mind having different markers, you could pick up a number of other (from what ive heard) better markers for the same price in the classifieds, have a look at:
impulses,
zerob e1 cockers,
(obviously) ifyou can find an e2 cocker,
angel ir3 (can get em for peanuts, but unless tere spitfired or similar they dont ramp),
angel 04 speed (veery sexy in my opinion),
A4 possibly in your price range,
if your willing to step up a bit in price theres a nice lookin silver proto for £200(a steal),
something like that, if you want an opinion, just post it up here and weel give you one (just remember that youll never get us to agree on the best gun lol
)
good luck
EDIT- youll find most of these with upgrades if you have a good look, so that might bring some of the more expensive ones into your price range, since you wont have to upgrade em yourself.