Here ya go, my opinions:
Pros:
Quick replacement if seal rips.
Solid round cuff that holds your computer or compass in place.
Quick-attach dry gloves instead of seals any time you want.
Solid platform around neck that supports shoulder straps comfortably.
Cons:
Neck hole is a little smaller, have to push your head through, some find it uncomfortable.
Dry gloves must be attached before you don suit, so you must don your gear while wearing the dry gloves.
Not inexpensive.
Personally, I find them well worth the expense and the cons. I do not use the attachable dry gloves, though--when I need dry hands I wear a pair of separate dry gloves with their own wrist seals.
theskull