if I am remembering right, in their day, the Legare 47 was a less expensive model than the Legare 400. Like a Honda Civic and a Honda Accord, maybe? I had a 47 for a while, I'd say it's a nice machine but the 400's a bit sturdier, so given the choice I'd go with a 400.
The most popular model is a fully restored CSM by one of the professional restorers; at least in my camp, that is -- I had the good fortune to get a Legare 400 restored by Pat Fly (www.angoravalley.com) when I "discovered" CSMs.
My Pat Fly Legare 400 remains my best running and favorite CSM.
A professionally restored machine runs just beautifully. Pat's not the only restorer, just my "local" one :-) but she's great! Several others are on this list and the other sock lists, too. There are also new manufacture machines now (just started last year), the NZAK -- www.autoknitter.com. Those are discussed alot on another yahoo sock list, sockknittingmachinefriends.
(posted by me this day on sockknittingmachines)