If you are a control freak (i.e. you think all your toys should move whenever you want) then they will not suit. If, like me, you think command and control/fog of war is important then they are great. They really give a good game, especially in the smaller scales. High command values are crucial but you can still see whole commands refuse to move for one or more turns - frustrating but in a realistic way. Combined arms really works. I play Russians 1943 and Italians 1941/2 with BKC and Pax Arcadia by Dark Realm with FWC and I love them to bits. Haven't played CWC but my Russian Cold War stuff is on the painting run at the moment.
I'm sure there are reviews out there (Wargames Journal used to plug them a lot) but I don't know of any specific items.