You should be OK with a bike, if fitted well all the wiring is hidden away, especially on faired bikes, and it's very difficult for a tester who doesn't know bikes well to spot what's OE and what isn't. That's one of the reasons the law's implementation is being delayed.
I have half a car kit on the dip beam of the Falco (cost me £20!) and the difference in road illumination is literally night and day
It's got though each MoT so far, I don't get flashed by oncoming traffic, Plod have no issue with it. I'd say get one, even if the wise lawmakers want to visually cripple us in a couple of years, it's worth it until then.