It all depends on the rider, I've seen guys who will go and go on their sportsters and guys with baggers that ride to bike night. It just depends on the individual. Are some bikes setup better for long rides, sure. But you can make a bike more comfortable for yourself then it might be for someone else. I wouldn't limit your riding length to an answer you get from someone. Ride as long and as far as you feel you can.

 

My wife did Ohio to Texas and back with me on her 1200C. Thats about 1200 miles one way.
We took 3 days,could do it in less but once over 500 miles in a day you start to get
tired and just want a hot tub.

The bike can go as long as you can. She has also done Tx to Daytona on an 883 about 12 years ago. Someone told the she couldn't take a Sporty to Daytona so proceeded to beat them there. According to her, it wasn't that hard, they kept stopping every 40 miles or so to get a beer and pee!

Ride long but ride safe & I second the T bag suggestion.