The figures I had were picked up cheaply from eBay and are from Old Glory. There were enough for two 12 man units, one of Ural Cossacks and the other of Peasant Cossacks.
Here is the Ural Cossack unit so far. I was advised that they had red lances, then told that the may not, but for now, they have red lances. Sorry if that's wrong.
Each set has a good mix of poses, and these are very well detailed figures. The Ural Cossacks have three or four poses, two holding lances poses, another that could be holding a standard (or icon), and figure with a musket or carbine (again, I'm not too sure about Cossack armaments). The officer is possibly from the peasant range. The Peasants have a good mix of poses as well, with swords and lances and various head gear. For both sets there are two poses for the horses, and these are suitably small - which looks correct.
Here's a picture showing the mix of poses.
While I was ordering the draught horses for my wagons (see last post) I had to make up the order to £10 as Fighting 15s have a minimum order, so I ordered a couple of packs of Cossacks to see how they compared.
The first set I opened was from Fighting 15 Miniatures, and are figures previously available from Oddzial Osmy of Poland. These are advertised as 15mm, come in four to a pack with two variant figures, and are for 1812. The horses are all one pose and its not a great pose. There isn't a lot of action on these figures - even though the figures are designed without the saddle they are still a little static. The saddle is cast on the horse and looks fine, but again with the single posed horse, they are all too much te same Plus they don't have lances - you have to supply your own. But they are cleanly cast, cheap, and they seem to mix size-wise with the Old Glory range.
As I said, these do not come with lances, but luckily I had a pack of Xyston pike/spear/lances that had been sitting around. I may even swap the bendy Old Glory lances at some point. Obviously these will need cut down to the right size.
I also ordered a set of Eureka Miniatures 7YW Cossacks. Now these are nice figures. They are also quite big as they are 18mm scale, meaning the horses don't look like steppe ponies. But as I said, these are nice. The riders are "split waist", which means the horses have legs attached and the riders are supplied from the waist up. They fit together extremely well, and with a few poses and horse variants, this should allow a good mixed posed unit.
Sorry if the pictures aren't clear enough.
So here are a few different Cossacks together. The Fighting 15s and Old Glory should mix quite well, possibly even in the same unit, but the Eureka, which are also for an earlier period, are maybe too big - even though they are the of those reviewed. These are (left to right) Old Glory, Eureka, Fighting 15/Oddzial Osmy. Next is the horses by themselves so you can see their relative sizes.
There's is some great info on Cossacks on a TMP thread here... http://theminiaturespage.com/boards/msg.mv?id=378273