You are correct that the CYMA 040 uses the VFC/LCT mounting system while the 047 uses the TM system for the front end. Not sure about the steel/monkey metal thing though.
Also have you seen a cool rusted steel AK? They look SICK, does this not make you want to get a cool weathered AK (not sure if that's Real Steel or airsoft, I found them on my computer and don't remember the context of how I got those)?
http://i.imgur.com/vwXJz.jpg
http://i.imgur.com/BPVYJ.jpg
http://i.imgur.com/VOc1G.jpg
As for other beginner guns may I suggest the JG or CYMA MP5, or the Echo1 P90.