I used one for two of my three births, and will do the same for this next birth. Mainly what I like about it is that it is deeper -- I like being able to submerge myself totally. It was also roomy enough that I was able to swim around -- meaning able to quickly float from one position to another. That was nice. Another thing is that if you find it unpleasant to be naked in front of other people, the trough, because of its depth and color, makes you feel somewhat covered. I also felt free to feel for the baby and massage myself in ways that I wouldn't if I had been more exposed. Other nice things are that it retains heat pretty well, and that it is easy to drain.
The bad thing about the trough is that it is made of hard plastic. The first time I used it I felt locked into a kneeling position (partly because everyone was watching and my reaction was to try to draw as little attention to myself as possible, i.e., remain still,) and my knees got very raw. The second time I was moving around a lot so it wasn't an issue. One thing you could do is get a blow-up thingy and fill it with water (so it wouldn't float), or just use a foam mat.
If you get one, get a new hose (or two, to transfer water in and out), and you will need an adapter so that you can attach it to your faucet, and test it before the birth so you are sure that you got the right adapter (is that the right word? I'm thinking computers. Well, you know what I mean.)