Hah!
I used to cruise arizona, california, oregon, washington, nevada, and idaho all the time on my cb350's and cl350's, I'd take off in spring and motor-hike all summer long, if that old 350 twin could do it there's no way anyone can say a 500 won't. (these were old 72-74 bikes I picked up for $100 or $200 and a couple of them I got for free!)
Had a friend who went with me one summer on a suzy 250 2stroke, he had no trouble, that thing did run into issues over the mountains a few times, on long up hill grades, but no serious issues.
Also, I used to cruise a little moped from kentwood mi to morley mi, roughly 48 miles, no problem other than the embarrassment factor, hey it was cheap ($5. could get you almost anywhere in michigan at the time, now it may take $15!) and fun.
Ride what you have, if your bike has issues after long cruises, fix it.
Right now, I'm kind of hesitant to take my 750 out for long hauls, just got it back together and want to break it in easy fbefore I head out for more than pushing distance!
Ken.