Well, I dive a Fusion, and I wouldn't switch for anything. I've had my suit for two years. I cave dive, which involves from time to time crawling around on limestone (not in the cave, but getting in and out of them). I've had two small leaks in two years. One was after several days of reboarding a boat where you had to let the ocean wash you up on a metal mesh swim step, and then get on your knees to let the DM take your fins off. I got a small puncture in the knee. The other was recent, and I have no idea where it came from (right shoulder). Both were easily and instantly patched. I have the sport skin, and use X shorts for pockets.
I've been reluctant to upgrade the skin because one of the absolute delights of the suit is its very light weight. It weighs no more than my 5 mil wetsuit, which means I can easily travel with it. It also dries almost as fast as a pure trilaminate suit, which the ones with the neoprene skins apparently do not do.
The pluses I see for the Fusion: No need at all for a custom fit. No air trapping; very easy bubble management -- THIS is the suit for anybody who's buoyancy challenged in a dry suit. Self-donning for most people (and for me, with thinner undergarments). Light weight, easy drying. Easy seal replacement and patching. (And if SiTech really does come out with their ring system, it will be possible to have a zip seal arrangement on the Fusion.) The Whites boots are fabulous if they fit you, although I don't know if I will ever use a rock boot system again. And I have to say that I like the fact that the suit comes with SiTech valves. My experience with the Apeks ones wasn't good. And finally, it's possible to lend or share the suit, assuming that the seals will fit, because the suit itself is extremely forgiving of different sized users. My backup suit is my husband's Fusion.
Drawbacks of the Fusion: At least with mine, it is a challenge to get their thick undergarments into the suit. (I believe they may have changed the cut on the arms and legs since I got my suit, which was not long after they first came out, and this may no longer pertain.) Footgear is a challenge, if you are a woman with small feet, although I have to confess I have neither used nor seen their new attached boot. But the biggest issue with the Fusion is pockets. With the sport skin, you have to do some kind of DIY arrangement for pockets (I use X-shorts, but I know someone who has actually sewn pockets to the Lycra and supported them with Velcro on the undersuit.) With the other skins, you can purchase pockets, but they are small, and the skin sags when they have much in them.
I honestly don't care what I look like in my dry suit. It has MANY more critical functions to perform than looking cool!
And to answer your last question, about neoprene neck seals, they also have pros and cons. They are warmer, don't cause neck chafing, are more durable and can be repaired before they are replaced. Because neoprene has limited stretch, however, a seal which will easily go over your head may well have a tendency to leak. This can be minimized with an Apollo bioseal, but if the seal leaks when it's new, it will eventually leak a LOT as it stretches out. Jill Heinerth, in the new cave diving book, said that neoprene neck seals aren't a good idea for women, because our heads are bigger in proportion to our necks than men's are, and so it proved for me with my neoprene neck seals. My husband, on the other hand, adores his.
You should also know that it's somewhat more difficult to find a shop to repair or replace a neoprene neck seal. We have a bunch of local shops that will do latex ones, but I had to send my suit out for the neoprene.
Hope this helps!