They're all good. Most of it depends on how you ride. No bike is good at everything. Goldwings and Electra Glides suck big time in stop and go traffic in the Texas' Summer. Sportsters are horrid for long trips with a passenger. Crotch rockets suck for long trips period. Low Riders are the slowest bikes in the twisties next to Schwinn's. Etc, etc. Some bikes are better jacks of all trades than others, but not everone needs a jack of all trades bikes.
A good example is a fellow freeper here who goes by Blackie. He traded in a Sportster for a Suzuki SV650, and from his posts he couldn't be happier. Now I have a friend who traded in a SV650 for a Sportster and he couldn't be happier. The difference is no doubt riding style.
From his posts here, I get the feeling that recreational rides through the twisties, with sport bike riders are Blackie's thing, and the light, nimble, responsive 650 is perfect for that type of riding. The Sportser is decidedly less suited for that ride than the Suzuki. No one likes to do that kind of ride knowing you'll be bringing up the rear, way rear. Being last is bad, but so far behind you can't see the other bikes is no fun.
On the other hand, the much torquier, heavier, Sportster fits my friends bill much better. My buddy was looking for an economical commuter bike that he can ride every day, and that could double as a 1up tourer. The 650 just can't compete with a Sportser for that kind of riding. The 650, while it has plenty of HP, is less torquey so the rider shifts more which isn't good on a 700 mile day. The 650 just can't compete with a Sportster with racks and bags for the cargo capacity my buddy needed.
On the other hand, if 2up riding is your thing, with any distance at all, you'd be a fool to buy either bike. For that kind of riding, you couldn't do much worse than either the sportster or the Suzuki. For that kind of riding you'd want a full boat tourer like the Electra Glide or Goldwing which are great touring bikes. You just don't want to get caught in a traffic jam, creeping along at 15mph for an hour on one. The complete lack of airflow at those low speeds is a recipe for heat stroke on one. They're not a good commuter bikes at all.
I just sent this to 2 of my friends. Good overview!!
I've owned over 20 bikes since '48 and have had one or more in the garage since, except for years '58 to '64 when I was in my Corvette, Austin Healey LeMans, Lotus Super 7 sports car period. :)
I've had three Harley's and the rest were Japanese, English, German and Spanish street and dirt bikes. I hate riding or driving on the freeway, it's so damn dull, give me a two laner anytime. As for two up riding; that's what they make Ford F-150 SVT Lightnings for. :):)
Here's a pic of my first bike:
