i'm 6foot4, and 130 kg's
had a gpx250 for 4 years; commuted on it every day, and rode on holidays (sydney-brisbane, sydney-south coast, sydney- central west nsw) regularly. had a frigging ball; apart fro the comments like i was doing unnatural acts to such a small bike. regularly got 350 k's to a tank commuting, and got 450k's to a tank touring.
it has been said any fool can go fast on a fast bike, but it takes skill to go fast on a slow bike. I have chased gsxr600's, cbr600's, zx6r's etc up a variety of nice twisties like macquarie pass, the alstonville range, beechmont road, tamborine-canungra road, bulli pass, grafton-armidale road etc and even got past them one more than one occasion (shocked those blokes; especially when we stopped at the end and they realised they had been carved up or buzzed by a lams 250!)
my 2 cents worth