Joe town, running your mower without the muffler is hard on the exhaust valve and seat, as the muffler works as a heat sink.
Harley makes a nice bike but it is pricey for the level of tech. A Buell is much tougher. Personally, I would get a KTM Duke
I also cannot say much about moto noise my scooter is an RD400, two stroke twin and when it goes by it sounds like two of the biggest chainsaws you ever heard. On the plus side I have the only one in the county I live in and it is cooling it in the garage undergoing a repaint.