Wargames Illustrated, has for the last three months had cover mounted giveaways, all new plastic miniatures. Here are those miniatures, undercoated, next to examples from other ranges for comparison.
Foundry French Resistance, Valiant US Infantry, Britannia 'not' Ross Kemp
Valiant US Infantry, Liberation US Marine, FAA German Infantry, Valiant US Infantry, SHQ German Infantry
The other plastics seem a little more mixable;
Wargames Foundry ECW, Warlord Games ECW
Wargames Foundry Rifleman, Perry Rifleman, Front Rank Officer, Wargames Foundry Officer
I think the pictures speak for themselves, out of the freebies that have come with WI, the Perrys and Warlord miniatures are compatible with their metal equivalents, whilst the valiant stuff needs to be pretty much kept to itself.
I don't want to have too much of a downer on the valiant stuff as the product is good, the price right and the models are versatile but they are what they say on the box - 1/72nd scale which on a six foot man is 25mm.