Yeah... I don't think Mara's Headhunter was a regular one either. And I have to agree that whatever stats the ships have in X-Wing series of games, I don't think they can be referred to as anything else than one set of (somewhat) balanced ships... and since the Star Wars Conversion team has (IIRC) said that they're not going to make a port of XvT for FS2_Open engine, they're likely going to be changing the ship balance a bit either, so we don't really know what to expect from the team... except that in the end result the Z-95 will likely be part of a balanced ship set. Might be different role from the XvT Z-95 with some different stats, or not.
My personal opinion about Z-95 is that it should be competent dogfighter with a bit better maneuverability than the X-Wing, have about the same maintenance energy level speed as X-Wing (BUT lower top speed with all energy allocated to engines) and it should have somewhat weaker shielding but only a little weaker hull plating than X-Wing (having same hull strength with a TIE/Interceptor was ridiculous, especially as the hull structure is about the same as X-Wing so there's no plausible explanation to that except for making the ship cannon fodder, of which there's no canon proof AFAIK).
I think Z-95 should be able to deal with a pair of TIE/ln's without dying on normal(or hard, depedngin how you want to balance the game) difficulty, but it should have problems while getting gangbanged by any more... this despite the fact that it's weapon placement and maneuverability are both worse than TIE/ln's, but higher hull and having shields should make it survive a 2-on-1 attack on regular basis with any skill in the cockpit. X-Wing, on the other hand, should be able to survive being jumped by a flight of four TIE/ln's with it's superior speed. I think I remember some claims that after it's introduction, the X-Wing became so feared amongst TIE pilots that it quickly became almost standard procedure not to engage X-Wings without at least 4-1 superiority in numbers, so that'd make sense to me as far as balance issues go.