If riding solo, I agree the Transalp (or Africa Twin) are great choices. Very reliable, and comfortable, too.

But if riding 2-up, I think The Weestrom is better than Transalp. Much sturdier frame, the Suzi carries more weight without starting to feel like its got a hinge in the middle (like both Transalp and Africa Twin do). Ever taken the tank off these, and compared - the difference is in fact huge.

The newest, 700cc Transalp gets close, but still doesnt quite match the DL on power and ability 2-up. All older 650/600-versions are far behind, especially on the highways the Weestrom will cruise effortlessly at 120-140 kms per hour, with all the luggage and everything, and thats when the Honda (especially 600/650) feels underpowered.

The Stroms cast wheels can take the abuse (that most of us can subject a bike to, I mean), and unlike spoked wheels, they wont require regular maintenance, spoke tensioning, etc., so unless you actually manage to bend or break them, and that´s rare, you dont have to worry about them at all.

You CAN do a RTW-trip 2-up on any of these bikes, its just that one´s got abilities, that are better suited for that purpose, than the others. Price is another thing to consider. All of them are very reliable, if properly maintained.

I dont think you can ride much ´off-road´ 2-up, and your RTW-trip luggage on it, on any bike. Your wife will most likely soon want to fly back home, if you try!!

Even bikes that are great for off-roading, would completely change with that much weight on board. And they would probably break subframes, etc, possibly even engines, ´cos they arent designed to pull such a load around the world.