Best M1A1 kit in 1/72 scale, avoid the Matchbox kit, the Esci M1A1 kit is their M1 kit with a few new parts, avoid it as well. Their M1 (Esci/AMT/Italeri) is the best one in that scale though. Avoid the Hasegawa M1 or M1E1.
BTW, many of Esci's kits are real nice and can be contest winners. I won 3rd place with my Italeri (ex-Esci) M1.