I owned a Buckmark, it was easy to cock but as suggested in a previous post not a very good trigger so I didn't find it that accurate. I chopped it in for a CP-1 which is a much better pistol.
The CP-1 can also be improved cheaply and easily to give it a nicer trigger and improve accuracy. Matt Brooks did a great review of the CP-1 in this month's Airgun World magazine.
I've modded my CP-1 with parts made by a guy called John Small who produces some lovely brass parts including a replacement muzzle featuring a sight post and silencer thread. I'll happily pass his contact details on if you want to PM me.
Jason