I have yet to go to a bike shop and actually try sitting on some different bikes, but I know that the Honda Nighthawk I rode in the safety class was a little small for me. Looking around online I find myself drawn to the looks of the standard/"naked" bikes. And I've been told several times that if I have any self-control to go ahead and get a bike in the 500-600 cc range because I'll get tired of a 250 cc very fast. So here's some of the bikes I'm interested in at the moment.
Suzuki GS500E
Yamaha FZ6
But I also find myself drawn to some of the older bikes I've seen on Craigslist...
1984 Yamaha Seca 550
1974 Honda CB750
What do you think?