It's just a typical sealant. Everything that can be said for that, can be said about any other artificially produced sealant.

Sealers typically last longer than cheaper waxes, but they don't offer the depth of color that a good carnuba offers. A lot of the comparisons they make are in comparison to cheaper over the counter waxes. A high quality, professional grade wax will last as long as that will, and give better depth. Good waxes are also easier to apply in my opinion.

I'm on my 3rd high quality wax in a year (just trying different brands in order to choose one I like) and I think I've settled on one. If you really want to put a quality product on your car, look in to Lusso Oro carnuba. It's been on my S2000 for about 4 months now, and water beads like I just put it on yesterday.

You might actually be fine with a sealer though, your car is one of the light colors right?

:edit: Oh yeah, guess why you have to wash your car with dish soap before you apply it. It's because if there's any carnuba on your car, that stuff can't stick to it. What's that tell you about carnuba?