I do not know about anybody else but it seems since the patch that has nurfed smg's with silencers there have been a lot of people sitting in corners with there LMG and a target finder attatched. Before the patched I got called out for using an mk 38 with rapid fire and grip attatched to it but now it is ok for everyone to roll with a LMG and target finder because smg's are no longer "over powered" so to say.
i use the Hamr with the iron sights. my attachements are fore grip, silencer, and FMJ. i use all LMGs with the iron sight. i've tried the LMGs with sight but they seem to suck to me with a sight. the iron sight just feels better to me.
Honestly its mostly the first two LMG's but EVERYTIME theres a TF on it.... to boot the first two are SUPER OP. First one takes two to three shots for a kill and has decent accuracy, the second is rediculously fast and accurate so you can't even aim before they pump you to the uviula with FMJ! I'm glad they didn't put TF on snipers or we would all be F*cked and they would whore the SVU too!