Several years go I got a couple of DRS from the drostore as well but I have issues with them.
They are fairly good on a mill but I have issues with the accuracy, especially on a lathe. When you set an axis in Imperial it does some weird rounding and seldom do you get the required dimension, it seems to be that the internal program is in metric and does a couple of conversions, with associated rounding errors, before it displays the Imperial dimension. On the z axis this isn't much of an issue as you typically have a +/-0.002 tolerance or more but bore tolerances are often much closer. I've found that for bores I usually just use the DRO for rough dimensions and the dial for fine finishing, kind of a shame but that's what I've found. The other issue is that the scales for the X-axis in a lathe should be 2 micron instead of the standard 5 micron scales but I don't know if those units support the higher resolution.
