Hi Steve I too have started looking at this issue
I do not have any problems with the one fitted to the fore deck of Alfresco, regarding hauling the rope through the gypsy.
The problem is stowing the rope in the locker as quick as the rope is recovered by the capstan, so that it does not jam on deck.
Because of that I only tend to use it inshore.when I have a crew or two.
I have started to look at the side deck capstans,
Muir had a smart one at the boat show and another 1000w unit is available from boatgeardirect, but they do not look like they would accept chain arount the drum and it would take a bit of modification to the boat to keep the motor dry,
I have started to look at the ones used on commercial boats.
The CJ Capstan has a self contained motor but they only use a 750w motor and recovery speed is quoted at 14mtr/min,
which is a hell of a lot slower than Dan or Sam recover the rope by hand, after we Alderney ring the anchor LOL.
Tom has just had one fitted to Illusion, so I have emailed him to ask him about that question.
One small point about your direct swap from a 700w to a 1000w unit. Have you checked the spec of the wiring on your boat?
I had to use very heavy cable on mine because of the total length of the cable.
You do not want hotspots inside the boat while you recover your warp and chain.
Charlie