I always thought of it as a 6mm set of rules.
We always played it in 15mm back in the day, pre-Battlefront, so we used mainly Quality Castings miniatures. Great set of rules, but it did take a very large table. I think it would be ideal in 6-12mm if you were aiming for operational scale gaming, as we were.
Once I get my workshop cleared out (new addition underway, full of junk), I do plan to get back to some modern gaming using these rules. There is sort of a post-Soviet civil war going on, after all, for which the Team Yankee figures will be ideal for. Luckily, I do have a big enough space for a good game.