175/200s:
KDX200, all the way.
IT200 is also a good bus. Better suspension and brakes than the KDX, but the motor and the handling aren't as good as the the green bikes.
XR200 rates a mention, even though they aren't a patch on a the KDX or IT in pure performance terms. But they work because they're so damn easy to ride, fast or slow.
Everything else is crap in comparison, although they may have attributes that particular riders like.
Talking 125s, the Swedish Husky 125s were all dogs.
The IT125 is a cool little bike, but it's really just a hotted up, 125cc version of the later DT175.
My 84 KTM125 promised to be brilliant, but is never rode it enough to prove the point.
TBH, if the best Pre-85 125 enduro bike isn't the 84 KTM, it is probably an 84 CR125 or KX125...
Pre-90, it's the 87-89 KTM or the 88/89 KX125, with the CR in third place. The RMs were all too peaky, while the YZs were too slow and/or too crap in the suspension (with 1988 being their high point).
A good mate owned an '86 WR125, and it was one of the biggest pieces of shit I've ever ridden. Way too slow to make the big bike chassis work properly, which added insult to the injury of the fact that it was damn slow.