Perhaps I should have clarified a bit.... by best driver on the market I'm talking about guys who throw 400'+ regularly. I'm just impressed with the Thunderbird because I can throw it 400' with a perfectly flat throw (no high speed turn). Usually to get that kind of distance I'd need a disc to flex out quite a bit. The Thunderbird will produce laser straight 400' throws dead accurately.
Obviously a Thunderbird will be a glideless clunker at 300' power. Some random newb picking up a Thunderbird for the first time will probably think it stinks because it doesn't cater to noodle arms very well.
I will also discount any posts talking about throwing very lightweight discs. Thunderbirds probably don't come in light weight, nor should they. When throwing discs under 160g you tend to lose sight of what the disc was made to do in the first place. A 150 Thunderbird would be a flippy POS made to appease the noodle armed crowd. My point being, I don't think someone should say a Thunderbird ISN'T the best driver on the market when they say they only throw 150g discs.
That would be like me ONLY throwing a 149g blizzard Boss and saying Bosses suck because they're too flippy. To get an accurate representation of a mold you should throw it at something near max weight.
I will definitely buy the Eagle and Teebird arguments too. I actually like both of those molds a lot and I think they're very reliable drivers. I just think The Thunderbird is a bit more workable at high speed and capable of better glide and distance than either the Eagle or Teebird. Thunderbird is a legit distance driver while the Eagle and Teebird are fairway drivers.