In my experience--and I am talking about not only my suit but many of the suits of friends, almost all of whom dive Fusions--the biggest issue is the sudden an unexplainable degradation of the latex seals. If you do enough research on both SB threads and the Whites site, you will see that I have actively investigated this problem. For some unexplained reason, the latex seals will suddenly start getting gooey. Once that happens, they have to be replaced.
In order to prevent that, I used to keep my suit sealed up as airtight as possible in storage. I kept it sealed inside a plastic storage box. I also used seal saver on them religiously. It seemed to help.
Notice the past tense in the paragraph above.
I later went with the new ring system with silicone seals. The silicone seals are super comfortable, and they require no care. The problem with them--at least in the first generation (I am told), is that they are fragile. After a number of dives with mine, the latex neck seal ripped in half when I was taking it off. I got a new one and replaced it myself before diving again a few weeks ago.
That trip just mentioned was a microcosm of the whole situation. We drove several hours to get to the dive location. While we were suiting up, one of the divers saw that his latex neck seal had gone gooey since his last dive. It had a hole in it, and it could not be used. He watched the day's diving from the shore. After the first dive, one of my silicone wrist seals ripped in half as I was taking it off. Fortunately, another friend also used the new ring system, and he had a spare latex seal. I put it on for the second dive. After the dive, I took it off and gave it back to him. Easy as pie.
I now have a spare (latex) neck seal and three spare wrist seals (1 silicone and 2 latex) in my bag in case of problems. The ring system makes them easy to replace.
By the way, in my investigation of the gooey latex problem, I subjected squares of the latex to every possible common contaminant we could think of, including the one (copper) Whites said was the cause. I could not find anything that caused a problem. I talked with 2 chemists who both said the most likely cause was that the latex was not properly created in the first place and its structure was breaking down over time. (I am not a chemist so I may not have stated that properly.)