One of the unfortunate aspects of modelling now is the tendency of modern equipment to go through upgrades, and the manufacturers of kits to do the same to the molds. While this is understandable -- current equipment often sells better than older equipment -- it does have the negative aspect that a segment of a vehicle's development history is lost.
The Abrams is a chief contender for this unfortunate practice. Back when the tank was relatively new, both Tamiya and Esci released kits of the vehicle.When the real tank was upgraded to M1A1 status, Tamiya modified the molds to reflect the modifications in the new tank (although it is also possible Tamiya just doesn't want to release it again).
Esci on the other hand folded as a company, and many of its molds went into limbo. While Italeri has recently acquired the molds (re-releasing the M60 series tanks -- the best representation of this tank on the market currently), the M1 was not one that was re-released (perhaps so it wouldn't compete with Italeri's already very good M1A1/A2 kit series).
When I came across this kit, I knew I had to jump at the chance to get this kit, model acquisition moratorium or not. While the Esci kit is inferior to the Tamiya kit, the latter is very difficult to find for some reason, and this kit isn't so bad to be unbuildable.
But it is far from perfect. Fit is adequate, but there is a general sense of sparseness in details. The real tank had its fair share of nuts, bolts, and the like, all of which are missing from this kit. The Esci kit was the first to market, so much of this detail may have been missed due to inadequate resources and references (Esci's T-72/74 and BMP series has the same problems). Also the kit represents the weld lines as recessed when in fact they should be raised. Finally, the stowage racks don't fit well (and one was shattered for that matter).
All of these detractions are easy to fix (Grandt Line makes nuts and bolts, weld beads can be reproduced with thin plastic rod, and the stowage rack can be reproduced with brass wire). Finally, I was able to salvage the correct style of tracks from an old Tamiya M1A1 to replace the questionable link-and-length tracks (which unfortunately do not have a curvature for the end connectors molded).
I am definitely looking forward to getting this kit together!