Those are all good decks, and as far as I know none of them have any major quirks. The A3340 is a 4 track deck that accepts 10.5" reels, and it may have the 7 1/2 and 15 ips speed option which means that you won't be able to play your 3 3/4 ips tapes on it.
The 4010 and 4010sl are old time versions of the A4300 7" reel 4 head auto reverse units. You need reel holders for the tape reels as those models predate the quick lock spindles, the frequency response is not quite as good and there are lots of interconnecting cables due to separate amplifier sections that can be troublesome, but if they're working then they are good machines.
The Pioneer RT-1020H is a very well built 10.5" reel machine and predates the RT-909. Super build quality, ac driven motors, reliable and does 3 3/4 and 7 1/2 ips speeds. That might be the one you want if the prices on all of the decks you listed are pretty close due to it's versatility with the speeds and reel sizes.
I had an AKAI GX-225, it was ok but had some noisy transistor issues and the build (while good) wasn't quite up to the standard set by the Pioneer or the Teacs. IMHO the A3340 (if the speeds aren't an issue) or the RT-1020H are the winners.
I owned a Pioneer RT1020H it is a High speed deck, 7 ½ and 15 the RT 1020L is Low speed 3 ¾ and 7 ½.