I only wear my drysuit for maybe six weekends a year, but it has lasted me since 1992 and is still completely waterproof! It is not breathable, but that isn’t a problem provided you wear proper thermal underwear – e.g. polypropylene base layer and fleece mid layer; the moisture passes through the underwear and you stay dry. I suspect that breathable materials do not stay waterproof for so long.
The latex seals have been replaced a few times, and if I bought another dry suit I would ensure that it had neoprene or “Glideskin” neck and wrist seals, at least. I also have a breathable dry-top which has neoprene seals, and while they are not quite so watertight they are adequately so, and they are much more durable.
I’d agree with another respondent that a front zip is convenient, even if it maybe isn’t quite so comfortable when bending over; I’d go for that option again.
You do have to be careful that the boat you are sailing in doesn’t have any sharp edges that could rip the suit, and maybe for that reason, damage avoidance, I tend to prefer to wear a 3mm wetsuit and a dry-top until it gets really cold. The wetsuit also provides a ‘body-armour’ effect, of course. If I could find a 5mm thick long john wetsuit with a smooth waist that the dry-top could seal onto, i’d probably wear that in preference to the drysuit even in the coldest months, maybe with dry socks.
The bits that still get cold are the hands. i’ve tried a number of so-called winter gloves and found they were either not warm enough or were too cumbersome. The best to date are cheap household rubber washing-up gloves (e.g. Marigold) – they at least keep the wind off, and if you wear thin polypropylene (Meraklon) gloves underneath provide a modicum of warmth.