Wife has the 07 Gear-Up (750, etc). It's a blast and a real conversation starter (which sucks if you're in a huirry), but imo it is not an interstate speed vehicle. While you COULD run cross-coiuntry if you have plenty of time, I would suggest it be done on back roads where the speed limit does not go far beyond 60 mph (and at that speed not for too long). It's more comfortable around 45 mph. We don't stray much from home with it yet, The appeal, for us, is the nostalgia, not the speed or comfort, kinda like a Bonneville (I'd love one for what it was and is but don't pretend it's anything it's not).
And you should know that it is more difficult to ride a sidecar rig than a m/c. I've heard folks that never ride say they'd consider getting a sidecar rig. A very bad idea, imo. There are different skills involved and it is a quirky beast (fun, but quirky). The editor (??) of Rider mag or some other mag that is out of NC died on one a while back- He was entering the highway (why I'll never know) with his, ran across the lanes (lost control?) and got hit by a semi truck. This man was a long-time rider, very sad.
The other 2 are capable higher- speed vehicles and I'm sure they are quite comfortable. But, there's nothing like riding a military-styled, arctic cami, Ural and having some dude on a Harley, wearing suspenders, who looks like Santa coming up to talk about your "old" bike, read the Ural on it and ask where it's from.
. Or better, having a family walk up and ask if there young kid (4 or 5) can sit in the tub for a second.
When I decide I can no longer ride, I'll have the Ural. Don't know if I ever want a trike, or a Can-Am. Maybe a trike but hte can-am still hasn't clicked for me. Hell, by then maybe we'll have the air cycles like on the Star Trek movie. Yea!