Seriously, these are fairly similar in nature. The first question, is what are you going to tow it with? If it's a van or SUV, than the TT is your only option. If it is a pickup, than the 5W is a valid choice. Generally, 5W are easier to hook up, ride better, have less problems with sway and have taller interiors. On the down side, they have 2 levels, the forward area tends to be cramped, and they are higher overall (more wind resistance).
Jerry, you will also lose most of your pick up bed with a fifth wheel. I have owned both and like the 5th wheels best. More total space and less total length because you have about 4 ft in the truck bed. As John said hook up and tow is much better but, a tt with the proper tow vehicle and hitch will tow fine. Just be sure you have the proper tow vehicle for either.
If you have the truck for the 5th to me there is no choice. Yes it does take up the bed but........ I have a saddle box for tools, a cargo box that sits behind the saddle and in front of the hitch, I carry an 11 gal air tank, 30 gal of diesel, leveling boards, tripod for the king pin and plan to put a sewage tank in there when I get the cash for it. Ya can haul anything that will ride below the sides of the box. I have had trailers before but there is now question about the fifth wheel. Pulls better, is more stable, easy to hook up and unhook, easier on the truck, can't even till when an 18 wheeler passes ya and sway is all but gone. You get a lot of liveing space for the trailer length. One more thing if you have a wish list. Get a slide. All the difference in the world for comfort and liveability.
Slides are great. However, before buying, make sure you see how usable the trailer is with all slide(s) retracted. I have seen some which you cannot eat a meal, use the bathroom, or take a nap with the slides in. In my opinion, this could be problematic if you ever want to do one of these things in an area where you cannot/should not extend the slides.
You hit the nail on the head hertig. If you can't use the thing with the slide in I personaly wouldn't buy it. I saw a couple that looked pretty good but the salesmen baulked when I wanted to see them closed.
You won't believe how much you will use the fifth with the slide in. When you stop for lunch, go potty, stop at a rest stop for just a quick nap, or campin in a place where there may not be much room. No, make sure you can go from one end to the other and use the camper with the slide in. It only takes a few seconds to open the slide but sometimes that's not practical. Something as simple as knowing it's gonna rain overnight and you are leaveing in the morning. I like to close the slide before it rains to keep the rain off the top of the slide so I won't have to go up in the rain to clear it off.