I fly Spitfires not only because I've always been enthralled by them but also because I most often find myself outnumbered in the LW MAs, sometimes even by several other Spitfires, and there's nothing else that gives you a better fighting chance in an outnumbered situation although I've had pretty good luck so far this camp in the Ki-61.
They are also good for buff hunting if you take the time to set up your firing pass.
And I think those are the reasons the Spit, even the XVI, has never been even close to being among my top K/D planes.
I'll add that being one of many on one while flying a Spit seems pretty lame.
So, to the Spit naysayers I say, grab a Spit and go really test yourself (4 on 1 or more) on a regular basis. Otherwise fly your "manly" pane in an unmanly mannor and just shut up.