I could not disagree more, I have a Prosport and a HW97kt, as well as a HW100, BSAr10 mk2 and an Air Arms s510tc, and I've got a tx200hc en route for Xmas from the mrs :-) my review was not a bias review from a Prosport 1 gun owner.
I'm not suggesting you're wrong in respect of your own experiences but the reason you don't see many 2nd hand prosports around is for the exact opposite! People tend to keep hold of them.
I don't find mine hold sensitive in the slightest, no where near as hold sensitive as my weirauch (97).
You must have been quite unlucky to be honest but then I've had similar issues with my HW97 despite the overall consensus that they're one of the best out there, mine shoots lovely now but I've had a rocky start with her, now she's tuned and I've found the right pellets a cracking rifle...but not a patch on the Prosport ;-) I've just furnished her with a new hand made stock from Andrea Gentilini (ginb) :-)