After damaging some of the plastic cogs on the stock Magura throttle on my Zero SR (it seems I was too heavy handed in changing grips) I bought and fitted a Domino Premium Full Twist Grip throttle as a replacement/upgrade.
I'd read one or two reviews on this throttle being better quality than the stock Zero Magura throttles and after damaging the Magura wanted to go to something a bit more robust.
I've been very impressed with the Domino. It has a reduced degree of twist to full open throttle compared to the Magura and a more solid feel and construction. It runs a five wire set up rather than the stock 3 wires of the Magura, the two extra wires provide a status of whether the throttle is closed or not (although controllers like the Sevcon can work this out anyway). I wired it to the Sevcon as a direct replacement with the following wire combination:
B- / Ground => Orange with Black stripe on Zero/Magura is the same as the White on Domino
Throttle signal => Brown on Zero/Magura is the same as Black on Domino
5V => Blue on Zero is the same as Blue on Domino
No need to make any adjustments to the Sevcon controller as the Domino comfortable handles the same voltage range used by the Zero approx 0-11V.
Here's some images of the Domino throttle. If you damage your existing Zero throttle or are just after a better quality unit give the Domino a try, you won't be disappointed.