The Tamiya M1A2 OIF is probably the easiest to build. It can also be built as either an Army M1A2, Army M1A1, or USMC M1A1. It has a few flaws, as all do, the biggest being the absense of anti-slip coating.
The new Academy M1A1 Iraq 2003 has a couple of problems. First, the track are the older angled block style from Desert Storm and earlier era. Secondly, the turret is too short and is crowded around the smoke launcher area. It comes with lots of gear and an extended bustle storage rack (USMC version, not US Army type).
Here is a review of each.
Tamiya M1A2 OIF: http://www.perthmilitarymodelling.com/reviews/vehicles/tamiya/tam35269.htm
Academy M1A1 Iraq 2003: http://www.perthmilitarymodelling.com/reviews/vehicles/academy/acd13202.htm
I like the DML M1 kits as well. Their latest USMC Iraq version is nice. All the DML versions come with a partial interior as well (driver’s area and upper turret). The newest version, M1A1 USMC Iraq comes with a full load of gear, PE screen for an extended bustle storage rack (though it is a US Army, 3ID rack, not USMC), and paper MRE boxes.
Dragon review: http://www.perthmilitarymodelling.com/reviews/vehicles/dragon/dr3533.htm
The Trumpeter kits are pretty nice as well, a little fidgety to build, but they come out looking really good.
Italeri has a new multimedia kit out too. It includes resin interior parts and a resin engine. Kinda pricy though.
Here is a review on it: http://www.perthmilitarymodelling.com/reviews/vehicles/italeri/it6438.htm
Here is a comparison of most of the M1 kits out there, compliments of Vodnik.
http://vodnik2.republika.pl/pages/m1-comparison/m1comp1.htm
That should give you all the info you need to decide which one you would like to build.
Good luck and have fun.
Gotta love when we get a “wingy thingy” guy to convert to armor!!