I too love the fact that not many are around. At Sturgis last year, seeing many, many thousands of bikes, it took me 3 days to see another. I saw 2 or 3 in a week's riding there.
I'm not one that's possessive about someone riding my bikes. If I figure they won't kill their self, then by all means, give her a go! With the Rocket, it's very funny to see folks' responses when asked if they'd like to try it out: a sheepish look, mild embarrassment, but turn it down nonetheless. For some, it seems it's intimidation at the size/power. For the Harley guys, I think its usually more to do with pride.
It would be nice to have some aftermarket exhaust support, however. When one of the only options comes from a party that doesn't feel the need to put an adequate finish on or even bother to make it reasonably fit, well, there just isn't much support.