M14 "SOCOMs" are tiny, they're not big at all. EBRs weight is all at the front and a fully length M14 can be unweildly if you're used to light small rifles
I've played around with a friends G&G EBR-L, it is extremely front heavy and quite awkward to move around. Built quality is lovely though and the range is very good.
I saw a guy once with a G&G EBR-S set up for a high speed setup- insane ROF. He wasn't moving quickly though!