Hi Vriez,
The very best these days? Wow... I'd have to nominate Dragon's late-tool kits, like the HA and the AIR, with slide-mold technology, PE right in the box, turned barrel (I think), and featuring fighting compartment detail... But they're expensive. I scored a couple on eBay over the last five years but they're rare to win for what you'd call a bargain price.
In comparison, the Tamiya M1A1 I'll be building here I won from a seller in Israel for about US$7 -- you can't walk past a bargain like that! Honestly, haunt eBay, search on "M1 Abrams" and manufacturer names, the chances are you'll score a bargain before long. And with a year to build in you can afford to be patient until you find just what you want.
Cheers, hope you'll join the brigade,
Mike/TB379