Well, mine is upwards of 230 million credits and 1v1 it can stand up to most ships below that price point, including fdls and the fed ships. It's quite well engineered too, but will also lose to those same ships depending on the skill, loadout and level of engineering of the pilots in those ships. Thing is, when I face the rebuy in my Python it's easily twice as much as the rebuy on my FGS and far more than the FAS. As a combat ship, I'm making a choice for the hell of it, but in heavy pvp where I know the rebuy screen will be coming a few times, I'm far better off in one of the other, proper combat ships, which are geared for similar, if not superior level of combat for less than half the price.
All that said, the only time I face the rebuy screen on my Python is when I allow it. It is well enough shielded and armoured to make a needed high wake when in trouble, and at a constant boost of 399 m/s it can disengage from combat against most of the heavies (obviously not cutter) within the instance. Against cutters, I am far more maneuverable with good use of boost and fa off. This won't let me "win" the fight against any self respecting cutter combat pilot, but it will allow me to avoid their main fire (and rams) plenty long enough to jump.
Still, mine is geared for combat for fun. Where it truly shines is in multipurpose missionrunning and for that I have to remove much of its engineered guts to make room for cargo. Mine currently has zero cargo space
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