That is a good inexpensive option. I see David taking good care of people. More money buys you more features and accuracy. The standard type of dro readout has trig calc, bolt circle program, bolt pattern, angle finder, and all kind of other features. On the cheap side of more expensive I recommend DROPROS glass scale kits. Very accurate and some good readouts. They might try to steer you towards magnetic scale kits wich are more money yet, but impervious to swarf and coolant. I like that company because they are reasonably priced but have great service. They also come with very good manuals in perfect English, not Chinglish. You can buy replacement scales separately for a reasonable price if you decide to move the dro to bigger machine. They have all kinds of tutorials to help new guys like us. They have done me right. Great, long warranties, I believe longest in the industry. Mine is 6 years. Most of their readouts come with a touch probe port, also a usb for future reprogramming as after all they are really little computers. Finally, they are Americans. So at least some of the money stays here. I am tickled with them, but not affiliated in any way. You can also go all out and buy top of the line brands. I wouldn't buy used personally though. Too much risk for me. I don't think they are any better/more accurate either. I hear good thing on Chinese made/sold dro's, but not their manuals,service,parts price or availability. I think a few dollars more here is well spent. This is all strictly my opinion, but check out dropros.com I think that's right.
if not it's close enough for google