We have (and live aboard) an '04 Charter Cats 450 (45') Prowler power cat. We love it, it's a great cat! I can only speak to the power cat, I know nothing of the sailing cats. The design is spacious and the only issue we have had in 3 1/2 years of living aboard and taking it out (almost) weekly, is in the turbo cooling system in the engines. There is a slight upward slant to the elimination line, and it must be drained after every cruise, or the salt water sits and corrodes through. I may not be using the right terminology, but hopefully you understand what I am saying, if not I will get my husband to reply in detail.
Other than that the boat is solid, handles well and is very comfortable. We especially enjoy being able to navigate from inside or outside. When we pull it for maintenance or inspection, people are surprised at her condition for her age. Let me know if you have anything specific you'd like to know.