Hi Simon, I would recommend them.
I bought my ball screws from them as well. The cost to buy them in Australia was $1800 plus post, linearbearings price was $640 delivered. I bought 25/5mm screw and 2 nuts per axis to load them up against each other. He does sell pre loaded nut's which have over sized balls in them, he calls them anti back lash nut's which is the way to go for single nut's.
I have inspected them and found no faults at all and they are nicely finished.
The are spoke of highly over on the CNC zone, with a lot of people using there ball screws, linear rails and also there air and water cooled high speed spindles.
Some times cheap is nasty, but in this case it's not.