I should of mentioned I'm considering this for a mill, although I doubt there will be much difference between the similar mill/turn models.

John, have you or Steve looked to see if there's any way to edit the PLC/Ladder onscreen?
I'm not really wanting to start faffing around with bodges to get the tool changer working, I'd rather just wire it directly (probably via some sort of buffer/relay board), and have the controller handle everything.

A bit more searching has turned up a manual for PLC programming on a GSK218M on the cncmaker website - http://www.cncmakers.com/cnc/Tech_Su...r_Manuals.html (scroll down to the bottom) and they also list a PLC manual and software under the Turn controllers for the 983 series (which appears to be an analogue controller). Going by the manual they use pretty standard looking PLC/Ladder Logic, which I can handle.
I've just installed the 983 software, and it only covers GSK 983 controllers, as you have to select the model when you try creating a new ladder, so I'm guessing there is other software, or you can edit the PLC/ladders directly on the controllers.

My other option is to use a KFlop, but I like the idea of the self contained unit, rather than having a motherboard/keyboard/mouse/monitor scattered around.
But given a 4-axis unit with an MPG mounted on it is in the region of £1000 delivered, I'd want to know it'll definitely do what I need it to, before I buy one. I could email the suppliers and ask, however I'm not going to get much response this week, given it's China's national holiday week.