Not 400four related but I bought some NOS Oxford heated grips for the GPZ as that's the bike that gets ridden in all the shite weather. One day, the starboard grip stopped heating, followed by a complete failure. It didn't take long to find the cause, it was the crappy electrical connectors: the pins had pulled out of the blocks.
I wasn't impressed with the connectors in the first place being not at all waterproof.
I binned those in favour of Superseal connectors and haven't had any bother since