Eventually got round to testing it.
Comes with a usb a to c adaptor so you can use undocked also has button stickers to put on your controllers which is a nice touch.
Did a quick firmware update via USB on the PC
Put in the usb at the back of the dock and put it in purple led mode for Pro emulation, changed a setting in the switch dash and it paired the DS4 no problem.
X and O were the wrong way round for A/B but this can be changed with a button combo on the pad.
Played Mario Kart and is sublime, no noticeable lag.
Well worth the £19.99