Thanks for your comments on this as always.
I know this ball in fact, I purchased on about 3-4 years ago after spotting it in the online store of an prominent UK high street chain calling itself a "Powerball" and wondering why we hadn't seen it before!
It was actually a 'rollerball' (not a Powerball) and you'll recognise it by the little "rocketship" symbol on the screen of the three function counter where the 'lightening bolt' symbol should be on ours. I managed obscene scores on my one too, simply because the counter is about 30-40% off the mark in terms of accuracy but it hurt like hell due to the vibrations at the higher speeds.
Mystery solved for sure, I wish I had seen the post sooner, thanks for the feedback regardless. BR Rory