This is like a confession box!..
I have also sinned.
A friend of mine built a 45 engine (750 side valve, iron heads) into either a Norton 16H or ES2 frame. it was rigid originally, not hard tailed, had the original girder forks and used a fat back wheel and tyre.
It was amazingly light and surprisingly quick, it handled very well too. The bumps would shoot me out of the sprung saddle, then I would kind of float above the bike with the saddle slapping my bum as further bumps bounced the bike up. But it held a line while all this was going on! Quite impressive really. He called it the Norty five, he also built a very nice rigid ES2 with girders, which was also very quick and nimble, he called that his sleazy two. The reg was 911 KNB which he said read as 9" knob... and he was.
I also rode a Buell lightning, but the one before the 1000 came out, I think it was 888? very nice competent chassis with lots of trick engineering. Handled like an RD250 or something, but was gutless even compared to my '98 M900 at the time.
The marque must carry the most baggage of any other and just don't buy into it because of that alone, so I know very little of the technical merits of them if they have any.