2013 FE501 Vs. 500EXC

You got it,the only other things I can think of are obviously the bodywork,and the Berg came with a plastic skid plate,Which in 13' the KTM did not. Also noteworthy,the Berg would have come with different fuel mapping,and muffler end cap than the street legal EXC.No fuel recovery emissions on the Berg. No carbon can,ect.My 2013 FE 501 came with 13/50 gearing,whereas the Exc came 15/45.This is how the bikes come in the USA.Some people argue the plastic airbox-subframe is more restrictive. It may be,but I'm not complaining. It's a pretty slick setup. At first the 4cs forks were a little sketchy,but since Ktm used them in many models after the 13' Bergs,all the suspension companies have come up with settings to dial them in. I like mine.
You can't go wrong with either bike.
The Berg is cooler.

Branding is the main part, I do know the motors sometimes are configured a little different as they produce different power at different RPM's, this could be from mapping as well different cams, not sure. They both are 510cc KTM engines 95 bore and 72 stroke.

Yes and I agree the berg is cooler