I got to rank 16 AT with 16 wins to 1 loss with Americans purely by spamming Rifle/LMGs backed up by the Captain's tier with AT-Guns straight into an Easy-8 or Jackson spam with two Soviet support players (One going a Mark Target doctrine and one a B-4 doctrine).
i think people just dont get captains enough. i see lieutenant and AA ht far more often. they have a much bigger impact when they show up since theyre really good AI and there wont be many vehicles at that point.
I wouldn't necessarily call the M1 AT Gun the best AT gun in the game - I still personally find the PaK 40 (when Target Weakspot behaves) to be the best AT gun in the game. But back to the USF AT. :3
id say its atleast the second best if not the best. i think raketen is the worst because of its ready aim time, range, RoF and tendency to shoot the ground. being able to retreat it is nice, but i actually dont like to garrison them.
i think zis is the 2nd worst because of its RoF, though the 6 man squad and barrage make it better than raketen.
its hard to say which is better between the pak and the 57mm. pak has a slight RoF advantage, but its vet ability works maybe 20% of the time for me now. if you have munitions for AP rounds, the 57mm will pretty much match the pak in pen, but having forward sight and 10 more range is a big advantage. theres plenty of times when a tank barely gets out of sight from a pak with 1 hit left. a 57mm would get that kill.
id say as long as target weak point is broken and if the americans have munitions to spare, the 57mm is better. itd probably be pretty much a tie for me if they fix weak point.