For what it's worth, here are my recommendations:
M4A1 - The DML kit is good, but is OOP and very difficult and expensive to buy. I recommend getting the Formations resin conversion and a donor kit for the lower hull. IIRC, the Italeri M4 is supposed to be the best donor kit for a correct lower hull.
M3A3 - I bought the AFV Club kit and it looks very good, although I haven't built it yet. If you want to build the earlier versions, look for the Academy M3 and M3A1.
M1 - For me, this was the most difficult to answer as there are several good M1's. DML, Trumpeter, Tamiya and Italeri all have Abrams kits out, but they all seem to have some problems with accuracy and detail. I have the DML and Trumpeter M1's and have looked at the Italeri (M1A2) and the new Tamiya release (which is nice, but is still missing the anti-skid texture). When I do get around to building an Abrams, I will probably kitbash the DML and Trumpeter kits. Hopefully somebody can give you a better answer than I did about the Abrams kits. HTH
Erik
"Don't fruit the beer."
Newest model buys:
More than I care to think about. It's time for a support group.