I haven't use one but I guess it really depends on what level of testing you are planning to do? Its a very cheap price and possible solution for you, but if you need more, seek a reliable tester.
I purchased an expensive kit from Seaward (4K) and it has been the worst piece of equipment I have ever bought. It has never worked properly since purchase and the support from Seaward has been appalling. I would highly NOT recommend.
There are several testers on the market that you could use including ranges from Megger, Martindale, Fluke, Metrel and of course Kewtech to name a few. They all have different features but look for something that will make your job easier without any problems. After all, your time is money!