I have a Hustler Super Z with the spring seat. I recently purchased my Z (33 hrs now on it) but it has the black seat. I noticed the Super Z's now appearing on the floor have a different style seat which is gray. Is this seat any better than the older black seat. I'm very disappoited with my spring seat. Maybe I'm too heavy but it does not provide and cushion or spring on any thing but smooth lawn. How much wait can the black seat adjut to hold as compared to the newr gray seat? Anybody have an idea?