Ah, OK, interesting.
Honestly, I don't think it's w&^%y waving, I believe that a lot of beginners just end up with what's cheap and available and they mostly seem to be the larger capacities. If folks are like me, they will be reluctant to commit too much money when starting out and the only 125/200's I've seen have been either new or nearly new, that and what is close too - may be more choice in Yorkshire, which seems to have some special tax regime for trials as 90% of them seem to come from there!
I'll keep looking - maybe something nearly-new that I can then sell-on more easily if I change my mind is another approach to consider.
Cheers