Half of the CYMA AK's are VFC/LCT style while others are TM style.
As for the CYMA M14, generally TM compatible but I've heard of people having trouble with installing FTK's (namely the Guarder FTK) into the CYMA M14. This is because of loose tolerances and it being a clone. You can still install an FTK but be prepared for lots of modification.
Note that TM, G&P, and CYMA/Echo1 M14 are TM compatible, G&G just went off and did their own thing.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE