My very first good bike was a Panasonic dx 4000 with all 600 ex from 1982.
I put many many 1000's of miles on that bike. I personally think the components were great for that era.
I replaced the rear mech at some point but I can't remember the specific reason.

I would put it on the same level as any second level group such as Triomphe, victory or even fiest generation Athena.

Nothing worked all that well back then.