Here are three simple tests to run on candidate lathes before choosing which one to buy:The ideas expressed here are only the opinions of the author.
1. Turn the lathe on, run it at various speeds, and note the amount of vibration coming off the headstock...less is better, both in terms of quality of the machine's design and the quality of product that it will produce.
2. Install a pointed live center on the tailstock and another point on the headstock, then run the two together and see if the points meet...meeting point to point is good. Then, turn the lathe on, and at low speed, note any wobble while viewing the headstock's spur point...wobble is bad. While you're at it, move the tail stock up and down the length of the lathe several times, locking it in place at the point to point head/tailstock position each time...do the points meet every time; or in other words, does the tailstock have left to right slop? If so (a cheap lathe characteristic), you're going to have problems if you switch your piece from a spindle hold to a chuck hold. I've noted more than a 1/16" left/right slop in the tailstock on many lathes.
3. Put a piece of wood between the head and tailstock points, lock the tailstock in place, then try giving the tailstock hand-wheel a few turns and note if the tailstock moves. Also, lock the tool rest in place and give it a good shove/pull…did it move? Cheaply designed lathes are notorious for having a weak tailstock and tool rest locking design. When you are turning a hard wood into the grain, you'll be very happy to have a quality lathe where all the lathe's pieces stay where you put them, while under hard vibration.
There are several additional things to consider, beyond these quality-of-design-and-manufacture issues:
1. Which speed control process to buy...manual belt adjustment, leaver pull, or electronic? No mater what anyone tells you, manually adjusting the belt each time you want to make a speed change is one big pain in the backside. While making a typical box, I might change speeds 20-30 times.
2. Size of work you want to produce...everyone says they only plan to turn spindles, pens and other small things when they are starting out...so, a small lathe is what you need, right? Well, if you can afford more, buy more. Otherwise, if you stick with the hobby, you almost certainly will be buying a second lathe (bigger/better) as your skills improve.
3. Low speed considerations...if you can envision the possibility of wanting to learn how to chase threads, be sure to buy a lathe that has the ability to run between 100 and 250 RPM. It is extremely difficult to turn threads in wood when the lathe is running faster than this.
Here's a reasonable game-plan for someone just starting out…buy a mini/midi like the Jet, Delta or Mercury ($280-350), with the idea of using this lathe to train on. If after a year you're still turning and enjoying the hobby, upgrade to a One-Way, Vicmarc, or some other quality machine.
Best regards and good luck,