I am entirely mystified as to why the Brewster Buffalo is getting so much hate from people. Of all the early-war US fighters, the Buffalo is arguably the best. It's got good manuverability (in fact, it was praised for this by Pappy Boyington,) equally on-par with, say, the P-40 or the like, but has one thing that neither the P-40, F4F, or P-39 had- a power/weight ratio and climb rate worth a hoot. Heck, I'd say it's fairly unique in that regard; an early-war American fighter that doesn't climb and accelerate like a lead brick? You don't say.
I wasn't paying attention to the forums when they introduced the P-39 (busy with school at that time, IIRC,) but I'd be equally as mystified if it received similarly harsh words. Considering that the P-40 has been favored by some good sticks who have shown what it can do, the P-39, which is arguably a hotter ship, should have been welcomed with at least some warmth. P-39 has similar manuverability and acceleration to the P-40, but is rather faster and has a cannon- why hate on that?
All in all, though, the addition of more varied and capable early-war fighters is going to make the Early and Mid-war arenas much more fun to fly in, because there will be more unique aircraft available in them. A relief of congestion in the Late War arena could be great fun- less furballs, more 1v1 or 2v2 opportunities. I look forward to it.
EDIT: And let's not forget that these aircraft have quirks of their own. The P-40 is, of all of them, a very stable and easy airplane to fly (even if it DOES have some quirky low-speed handling characteristics,) the P-39 is a right naughty girl at low airspeeds (read: HOPE YOU LIKE STALL HORNS), and the Buffalo... torque. Oh, dear god, torque. Until it's released in AH the only other sim I know of that's modeled the Buffalo is IL-2, and even though AH's flight model isn't quite as exacting as IL-2 in that regard, if it's any indication, managing torque in that bird is going to be, ah, interesting.
My point is, the early-war aircraft are now being expanded into a vertible "stable" of their own, rather then being the odd children out amongst a horde of late-war uberplanes. More planes to fly with more planes to fly them against, and all of this in machines that make you work for your kills because you don't have nearly as much spare energy to fling around.
Perhaps I'm an optimistic fool, but I'm excited. <3