Hi John,
I have the Jet 1642 and it is a very good lathe.
The only drawback is the size of bowl that it can turn. In theory it can turn a reasonable size as the headstock turns at 90 degrees to the lathe bed, but the stability of the bed, and vibration/noise make turning something too big difficult.
Recently whilst trying to turn a large elm burr, my banjo snapped in two, but this had more to do with the angle I was turning than the quality of the machinery.
In summary I cannot fault it for everyday pieces, and medium sized bowls, but I am wanting to turn larger items, and will really need to invest uin another machine.
Currently I am looking for a Union Jubilee or Viceroy lathe, but more of a bowl turning than one with a long lathe bed.
If you may at somepoint want to do larger pieces, then perhaps you should go up a model, and get something with a cast iron bed. May be cheaper in the long run.
Hope this helps.