Not too shabby.
I grabbed these because they were cheap, mainly for hobby use. For ten bucks, these things do way better than expected. Play is limited to a bit of axial rotation about the slide. There are two set screws you can adjust to eliminate any play normal to the axis of the slide.

I borrowed a pair of Mitutoyo's at work and decided to compare their accuracy. These calipers were generally within a thousandth of the nicer pair, so their accuracy is well within what I need. They do not always come back to zero when I open and close them (+/- 0.001"), but since they're I really don't care that much. So for those of you that like things quantified, I would give them an accuracy of around +/- 0.001". If you need to measure something with more accuracy, then a 0 pair of Mitutoyo calipers will probably suit your needs.

All in all, a very decent pair of calipers for the money. Even came with an extra battery. We'll see if these last long enough to use it...

Defective
Might be a good deal for the price if it worked. Mine came and it was already turned on. When I try to turn it off it doesn't and actually adds to the number on the digital display. I tried the spare battery just in case this was a low battery problem and that didn't help.
When I could get it to work it did appear to be accurate 80% of the time. Sometimes though it would go out of whack.

I really like the price and the product seems good, which is why I gave it 2 stars. It seems sold and I figure that I just got a bad one which is possible with any product. I'm thinking of ordering another to see if I have better luck with the second.

So far, a failure!
I've yet to get this caliper to work correctly. The numbers/measurements go all over the place! It is not accurate, but then again it may be dead batteries. I asked Amazon for some replacement batteries and was nicely told NO. I can update this review if I am made whole with my purchase.

Just What I Needed...
I was concerned I might not be spending enough to get what I needed, but this turned out to be a great decision. For this is a steal. You can spend a lot more on a set of digital calipers, if you need higher grade steel or finer measurements, but for the typical garage-mechanic or ammunition re-loader (like myself), this fits the bill perfectly. Measurements are consistent and, as far as I can tell, accurate. Construction is surprisingly good for what you're paying though the thumb-wheel feels a little flimsy and requires more downward pressure to engage than I'd like. I've just started using the serrated thumb indentation on the readout module instead of the thumb-wheel and that solves that little nit-pick. The display is big and easy to read, which I like very much. The battery required is, thankfully, a common one that can be picked up almost anywhere that sells "button" batteries (there's few things more annoying than when something like this uses some obscure battery that Radio Shack has order for you). With proper use I can see this caliper lasting a lifetime. It won't take the proverbial licking and keep on ticking, but again, for the price, it's probably just the electronic caliper you've been looking for.

Nice tool for the money
You have to be very gentle with this tool. The sliding wheel seems a little fragile, you need to be careful. This is a very good caliper, it comes with a spare battery, nice molded case, a very modest instruction sheet. Very easy to use. Cons: It feels like it needs a little lubricant but the instructions don't say anything about that.