I dislike dry glove rings for roughly the same reasons. They get in the way on commercial work and get beat up pretty badly reaching into confined spaces. I also dislike them for technical diving as it makes it harder to reach between deco bottles and reduces the lenght available on my forearm for a slate and bottom timer.
What I discovered is that the my hands stay just as warm in 5mm wet gloves provided:
1. that their seams are intact (no water flow through the glove itself),
2. that the gloves have a strap to secure the cuff (again to reduce water flow in and out of the glove) and
3. that I wear warmer undergarments
It does not matter how warm your gloves are, if your core temp falls, your body restricts circulation to the extremities in an effort to keep your vital organs warm and delay the onset of hypothermia.
So...if you can reduce water flow and beef up your core insulation, your hands will stay toasty warm. This has held true for me during working dives with several hours spent in 50 degree water, technical dives well over an hour long in 40 degree water, and on ice dives in the 30-45 minute range in 33-35 degree water.