You remind me of my Uncle who when I was a kid would only ride British motorcycles. Bonneville's, Commando's etc. He hated Japanese bikes and referred to them as Crapanese. 
One fateful day he took his latest Bonneville in for service and they convinced him to test ride a Suzuki GS850. He came home with it, never had a British bike again, and thought that Japanese bikes were the best thing since sliced bread! 
I've not owned a British bike.
All Jap when I bought my first age 16. It was just old men who rode Brit bikes that leaked oil and wouldn't start.
However, I'd be happy to own a modern 3 pot 2500cc Triumph Rocket 3. 
I often rode my mates Dunstall Norton Commando when I was 16 - until I got caught.
At the time, the handling was a lot better than Jap bikes, but the vibration through the bars and foot pegs was unbearable and forever causing bits to come loose and fall off.
Basically,it was a couple of decades out of date, and the build quality was atrocious. Just like most British cars at the time.
I borrowed a Trident for an hour (also when I was 16) and that was a lot better, but still felt like an old steam engine compared to Jap bikes.
Having said that my first Kawasaki triple blew the crank seals at quite low mileage which rendered the engine scrap.