I've been researching a tower for my boat for over two years, the Monster Tower is the one for me. Don't get me wrong, there are many cool towers out there, but as a total package, this thing is awesome. It looks great (even better in person), is totally silent, is a great ride, AND the price is great.
I rode behind the Monster two weeks ago and it is solid. I have a good friend with a Super Air and a friend with an X-9, and the ride is evry bit as good as those.
Good luck with you're search. I plan to install the Monster on my '95 Maristar in a few weeks. Hopefully I'll get some pictures on the Monster site.