I know of PLENTY of Angels that have gotten +/-2 fps or less over a chrono, as soon as the packing grease is shot out of the gun, takes 2 cases. I think the Excal has more potential, based on the design, but... let's keep things straight here. As for dirt in the hammer area... I can't see how, unless it was covered in sand, or if the breech was opened up while winds were blowing sand everywhere.. I've never seen that as being a problem with mine.
There will never be a "best gun." Different people prefer different guns. All high end guns shoot about the same, so it all goes down to how the gun feels to the user, and what little extra's they want. No sense in trying to prove that one high end gun is better than another, it'll never happen.