I think it comes down to what you are willing to pay? and the features you want. If you are looking at something like £20-30 then there are a lot of choice and it will be the chinese boards if bought in the UK.
If you need features like more than one relay, charge pump and or a 0-10V output for spindle control then you are looking at spending a lot more.
There are some good boards like the PLC4X from Zapp, the PMDX from pmdx and so on, but because you are asking this question means that you may also need support, so also consider this as well.