The reason so many people recommend the EX500 is because it's been around for years and they are plentiful on the used market and easy to sell to the next new comer. They are also a fairly docile bike. If your looking into a used one, stay away from the ones ridden by kids because they usually rev them too high and don't keep up with the valve adjustments leading to cylinder head problems.
You shouldn't be surprised at the praise for the older bikes. Where do you think the reputations for all these companies was forged? The Japanese have always had tremendous pride in their workmanship and they value their good names. Bikes of the 80's in particular are often overbuilt with the idea toward longevity.
I have to be honest, for your size I think a Nighthawk 750 would be an excellent choice. It is not an intimidating bike yet will continue to thrill as time goes by. That engine is reliable and there are plenty of them out there. If you get one, do yourself (and your mechanic) a favor and get the HondaLine center stand kit that is available for it.
