I ride a lot of different bikes (not all mine, of course), but my own ride is a CBR954RR, and I regularly ride a friend's Ducati 1198S and KTM690SMC (that thing is awesome!), ridden a few Ducati Monsters, BMW R1200GS, F650, R1100S, K1200, Kawasaki ZX-10, ZX-9, ZX-6, Ninja 1000, Suzuki GSXR1000, a couple of cruisers...
I honestly find sport bikes more comfortable over a long distance. I can move around a lot, rest my chest on the tank, sit up, sit back on the back seat... Basically, I can get into all sorts of positions to rest, but the typical sport bike tuck is fairly comfy for me.
By contrast, I dearly love the KTM690SMC (in fact, I'm buying one), but I hate it for long trips. You're exposed to the wind, your riding position is fairly fixed, and I find myself getting sore much faster. Same with the Monsters I've ridden, and cruisers too. Cruisers, in particular, I just can't handle for long rides.
The BMW K1200GS, probably, is the most comfy bike I've ridden, but it's not really my style, too darn heavy, though it is an epic machine. Most days though, given the choice, for a 10hr day ride, I'll take a super bike. I'm in my 40's, for the record.
Z...