I've been cave diving in O'Neill 3/2 Reactors for 15 years. I like surfing full suits because I can wear them for surfing, freediving, scuba diving, and tech and cave diving. O'Neill products are durable. If you need extra warmth, adding a hood or hooded vest (which prevents cave dandruff) and adding pocket shorts will put extra neoprene over the heat loss areas. I like the super flexible neoprene and their slickness in the water. I prefer my 3mm O'Neill to wearing my 5mm ScubaPro or my DUI drysuit.
That said, Deep Six products are designed by a professional cave diver. I'm excited by Chris's wetsuits.