Yeah, filter systems are oversold by some companies. The type of filtration doesn't make much of a difference. Filtration time is arguably more important.
As for Premium Leisure, you won't find too many people who recommend them as a number one choice. There are much better options out there for similar pricing. Most people will tell you to stick with companies that have a longstanding reputation for quality, reliability, energy efficiency, and customer support. Premium Leisure does not have that reputation. They don't necessarily have a bad one either though. If you find a model that you like, it fits your budget, is comfortable in a wet test, and you feel good about the dealer, then you probably are going to be fine.
What model are you looking at? Price? What are you comparing it to?
