If you're wanting to take your bikes with you, you'll need a "toy hauler", which has a "garage" space in the back, with a back door that turns into a ramp that you can ride up into the unit. That's what my wife and I are looking for, too, but we're probably going to wait another year or two before we get it.
Many will tell you that a dually would be better, since it has more traction and is less likely to be "pushed" sideways in heavy winds, however, I understand not wanting to get one of those and keep the single rear wheels, since I did the same, and got a 2500HD (3/4 ton) instead of the 3500HD.(1 ton). Though, I figured if the guy who had it before me could pull a 27' race car trailer with extra parts, and bragged that it towed like it wasn't even there, over the mountains around us, then it should be able to handle any toy hauler we want, plus the price was so good I just couldn't pass it up. It's done fine, so far. The main reason to get a 3500 (1 ton) is to be able to tow more weight, but we don't want or need a 40'+ toy hauler, anyway, so won't need to pull that much. It's up to you as to what you want, though.
