Are Promaster SLR lenses any good?

Such as the 200mm 3.3?

It seems that there were three tiers of lenses back in the day:
Tier 1: Lenses from camera manufacturers. These were generally the best (and costliest);
Tier 2: Major off-brands such as Vivitar, Tokina, and Tamron. Lower quality with exceptions, and lower price.
Tier 3: Minor off-brands such as Promaster, Focal (Kmart), Quansomething (Ritz?), and many others. Lowest price, and unpredictable quality.
So for your 200/3.5 lens: It's a gamble. Prime lenses are generally sharper, so it might be good. Give it a try, but I don't suggest paying over US$5 for it. Non-OEM lenses are worth little these days.

Mark Overton

For what mount, AF or MF? Later AF Promatser lens were for the most part rebranded Sigma or Tamron, early MF lens could any of a number makers, the only 200 3.3 MF lens that comes to mind was made by Chinon and sold under a variety of labels, ok lens, I would not pay more than $30.

I paid $20 for a Nikon AI one, mainly because my 200mm 4.0 nikkor ai is so shoddily built.

Only a guess, not many 200 3.3 out there, more common was 2.8 or 3.5., so likely a re-branded Chinon, my limited experience with Chinon has been positive, good build quality, ought to be fine stopped down. The same lens was sold in M42 and K mount as Sears.