I bought one a couple of months ago, after a lot of research, and have been
extremely satisfied. Thought long and hard about a Powermatic 3520, but
ended up going with the Jet. The extra swing would be "nice", but not used
often enough to justify the addional cost. Also. looking at the 2
side-by-side, it's pretty apparent that the 1642 is a downsized 3520. My
previous lathe was a Jet 1236, and met all my expectations, so I had no
qualms about another Jet.

While the advantages of the 3520 are pretty obvious (swing, weight,
Powermatic brand), there are also a couple of possible shortcomings vs the
Jet 1642. The Powermatic does not have a hollow tailstock. so it can't be
used as easily with a long boring bit for lamps, etc. Also, indexing is
accomplished with a reportedly cumbersome add-on. making some tasks more
difficult. Neither of these is a major issue, but did factor into my
decision.

Ron