Wouldn't look out of place I don't reckon Craig, Super Rockets had them (or some did anyway, I never know quite what went or should go on what year, they're all 'AIOs' to me!), they look quite good and of course primary side access is better and there is one less shiny bit to have to wash if you're into that stuff, which I'm not.
I have siamese systems on three bikes and I prefer them for the above reasons. I doubt they are a performance improvement because you usually end up with unequal lengths, but there are so many variables. . . . I started siamesed on my A, went twin pipe, and then came back to siamese, which is how she's staying. Runs nicely on it. I've heard it said that if you're running twin carbs, use twin pipes, but I break that rule on another beast and she goes fine too.
As for the sound, my A is standard sort of tune, iron head, 7.25:1 and it sounds nice to me. I have a pattern Goldie on there. Sadly or perhaps not it's quieter than the outrageous things of our youth, but still a respectable rumble, which can become almost a roar. Obviously doesn't have the crack of a higher compression engine with a lumpier cam, but not bad for all that.
