That's a good article overall, but there are a number of points I'd disagree with:
You need a much looser suit than a diver would wear. Otherwise you will be miserable.
You need a more *supple*, and thus probably thinner (for the same temperature of water) suit. A wetsuit fits correctly when it is not too lose to allow water to slosh around inside, and not too tight to constrict circulation. Conceivably if you are going to be caving in the wetsuit for a significant time *before* getting into any water, you'd want one that is looser. (I would still opt to go for one that is thinner, and pack it in a pack.)
Besides the ways of getting a wetsuit that are mentioned in an article, a way that was suggested to me is to go to a dive shop and ask if they'd be willing to sell rental suits that were ripped up by previous customers (and then patch the damaged areas).
Never, ever pee in a wetsuit, even if you are immersed in water. The urine will replace the thin film of water between suit and skin, and cause irritation or even extreme pain in some situations. And when you get out of the cave, the normal reek of a hot, sweaty wetsuit will be increased to truly breathtaking levels.
Sorry to bring this up again, but I (and also probably all divers in the world) disagree strongly with this admonition. When you get cold, blood is shunted away from your skin and to your internal organs. Your kidneys see a higher liquid volume and do their work, producing more urine (this is called cold diuresis). The urine goes to the bladder--where it must be kept warm at the same priority as the bladder that contains it and your other vital organs! By eliminating it, you automatically do a lot to avoid hypothermia. By putting it between your suit and your skin, you heat your skin and help yourself to stay warm in another (less significant) way. In a wetsuit, water seeps in and out at the edges, so if you are submerged in water for a significant time, all the urine will circulate out into the water. Obviously peeing in your wetsuit while walking through dry passage or when just coming out of wet area into a dry area is foolish, and can produce the problems described in the article. Doing so could also enable the urine to drip out and contaminate drier parts of the cave, where new colonies of bacteria could grow interfere with other life in the cave.
(It is a common, and correct, wisdom that urine is sterile, which is to say that there are not many pathogens in fresh urine. But the reason why medical professionals generally do not recommend washing wounds with urine is that the urine can be a *food* source for bacteria. In general, a caver should only pee into a dry cave environment if it is necessary to ward off hypothermia or to restore necessary concentration to safely exit the cave. When this happens, there has been a failure of planning. An empty Nalgene bottle has many uses--if not used as a pee bottle, it is a weak flotation device, a trash can and receptacle for the beer you find in the cans you pack out that were left by mofos, a sharps container, and a water container for situations when you have lost your water bottle and need to gather water from the cave.)
Avoid one-piece or hard-to-remove wetsuits. You need to be able to attend to bodily functions without assistance. Thin surfer suits may work, but you may need assistance pulling down the back zipper. One male caver installed a Velcro-closed "pee port" in the front of his surfer suit.
Or you could install a cord on the zipper to make it easy to reach behind and operate it...
I agree that wetsuits that are difficult to remove (such as the NRS Farmer Bill) should be avoided. But I think that, beyond the question of *whether or not* it has a zipper, what is easy to remove and what is hard will depend on the individual caver.