I've not been to sea in one but have had the opportunity of a thorough inspection. IMHO they are keenly priced and it shows in the finish, and lack of attention to detial during fitting out. Their tubes seam to "feel" cheap, i'm not sure if they use thinner material?
When i enquired they were limiting their market by only offering certian engines (not Mercury) this may have changed, but also put me off.
I've heard conflicting reports about the customer serivce they are able to offer - which is a concern, but may be unfounded.
I think they offer value for money, and as such have a market place, but are a long long way from the quality of Osprey (i would say that would'nt I) Scorpion (Of course, i hear you shout) etc. and still not up to that of more sensiably priced manufacturers such as Ribcraft and Humber. I don't think they are any cheaper than a Solent, which in my experience are a better built boat with a proven hull and renound customer service.
As i've said - this is all my opinion, of course. I await the numerous replies from happy ProSport owners!