Well, Devil5O5 and I winged up in spit 14's about a month or two ago, and we wailed the crap out of some F4U's, 109's, and a lala. Pilot skill and team work might have had something to do with it, but neither Devil or I have logged many minutes in the Spitfires. And its unarguably easier to fly than the Ta-152.
All evidence I've seen (stats being the exception) suggests that its worthy of a 1-2, MAYBE even 3-4 perk price. Its not as manuverable as the other spits, but its more than manuverable enough for the games that its speed and climb rate suit it for. So lets just say the jury is out on this one.