I just bought Horizon Wars...
The rules seem promising and I actually have other interested parties in my gaming group.
In most games, the smaller the scale the larger the scope: 28mm is for platoonish games, 15mm for company-sized games, 6mm for battalion and so on... Table size, number of elements (bases with either a single or several minis on) and game duration remain more or less constant around 4' to 6' by 4' (120cm to 18cm by 120cm), 30 to 50 elements and 2 to 3 hours a game.
After having been exposed to games like Mordheim and more recently X-Wing, I've come to appreciate games with a limited number of elements (a dozen) and short games (around one hour, allowing for two or three games on ), but have been missing the miniature diversity (infantry, ground vehicles, "air"-crafts all together on a table) of larger scope "combined arms" types of games...
Horizon Wars goes for a more "skirmish" (from a number of elements point of view) approach which should allow to enjoy varied "combined arms" miniatures while remaining in the realm of fast paced "skirmish" games...