In addition: ALWAYS set the speed to the slowest setting before stopping it. Just trust me on this, one day you'll forget you left it on 2,000rpm last time you worked on a pen, and when you start it with a rough bowl blank it'll jump around the shop.
While Duncan makes a good point in his post, I'd like to add... Make a point to always check your speed before mounting your piece.
Do it religiously, regardless of what you are mounting, make a practice of checking your speed before you mount ANYTHING. In the event you forgot to slow it down before parking it, you can always turn it on empty and slow it down, without large chunks of wood flying across the shop. If you make this a practiced step in preparing to turn ANYTHING, it comes more naturally, and you're less apt to forget. I know, I will at times turn my speed up during final sanding at higher grit on pens, occasionally part pieces while holding them in place at speed, finish the bottoms on pieces at speed, and forget to turn my speed down. Turned one or two on that were out of balance, spit a couple out in the floor, had the lathe jumping all over while trying to shut it off with my toe, because I sure as hell wasn't leaning over in front of it to reach the switch. So, I just got in the habit of checking my speed before mounting anything. Turn it on, slow it down if necessary, then mount the piece.
The Reeves Drive is a pretty solid system Steve, not a lot that can go wrong with them if they're not abused. There are a ton of lathes out there in the world that utilize this drive system. You may see some end play in bearings over time as the drive exerts forces opening and closing that will cause some wear laterally along the shaft. See that in my Grizzly, and have the bearings to replace them one day in the near future. This won't affect your turning in most cases as pressure applied with the tailstock holds everything in place and it doesn't affect anything.
For a Jet, in that condition, with the extras, it was a pretty decent buy at that price. The additional bed length isn't a bad thing either. While I personally haven't had a project that needed the additional length, I had a neighbor ask if I could turn some table legs, for cedar cookie tables he was building. He built a few taller tables with a shelf, and there I did use pretty much the entire bed length (40" on mine) on a dozen or so legs.
Congrats on the new lathe, I'm sure you're enjoying!