Depends what you want from a bike, Buster1. If you want a clean standard bike to ride, polish and show buy the '16. They were only made for a year, they have the kudos of being the first, there arn't that many about and at 20 yo they are elegible for classic shows.

Parts can be sourced for most things, some from Honda themselves although you might need to get friendly with the local dealer to search for back stock. Not much is available to tune them, most owners fit barrels, carbs and pipes from '18/'21s for more power.

Mc18/'21s are more plentyful (common??? ) and are more tuneable with wider 17" wheels and better suspension on the '21 models.
'28 were the last model and are expensive to buy and de-restrict. I believe a '16 is 10kg lighter and 5bhp more powerful

I've had my '16 for 2 years and it's been on track days, road runs and it is going to the Isle of Man this year.
If you want to tune and modify, buy a '18/'21/'28. If you want to ride, have fun and smell of 2t, buy the'16. You won't regret it.

john.
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