I did 95K miles on an old 400N Superdream. Very reliable, not very sporty, crap brakes and suspension compared to modern bikes, but if all you want is a daily hack then it was great.
Change the oil regularly as mine didn't have bearings in the head for the cam - it just relied on running in a bed of oil.
The only problem I had was the bolts going into the engine casing holding the head on etc stripped their threads and I had to get them helicoiled.
The thing survived me dropping it twice, being run over by a woman parking and 6 years of commuting long distance.
The trouble is, for not a lot more you could by an old ZZR600 which is a much better bike.
'The great fallacy is that the game is first and last about winning. It's nothing of the kind. The game is about glory. It's about doing things in style, with a flourish, about going out and beating the other lot, not waiting for them to die of boredom.'