Are Vivitar lenses any good?

I don't know much about cameras but my boyfriend likes to collect lenses. He uses modern Nikon DSLRs but has an old Canon that uses film. I came across a Minolta X-700 and some Vivitar lenses for $50 and I'm thinking about getting them for him. Are they worth buying?

I don't have experience with either of these two lenses. But I bought a Vivitar tripod recently and it was the biggest waste of money ever the quality was just shocking thats just my opinion and maybe there lenses are ok. As for the Minolta I have heard that they have some very good film lenses. And are definitly worth a try.

Back in the days of MF, Vivitar sold some very nice lenses (they were a distributor and put their names on other's kit, but what they used was generally of good quality).

If the lenses are sold as a package with the X-700 (a VERY nice piece of kit) they're probably in Minolta MD fit and won't fit a modern Nikon. He'll have a fine film outfit, though.