I tried both on my Stealth 2.0, and I have to say I much prefer the ring bungee system. To be fair I boat dive almost exclusively so my tanks get clipped on before I jump, and often stay clipped until I've climbed the ladder.
I guess though this really comes down to personal preference rather than one way being much better than another?
As a side mount cave diver, I am very picky about tank position and profile. My major beef with the Dive Right ring bungee system is that the tanks are almost always low as the ring, bolt snap and quick link, along with the limited stretch and upward pull of the actual DR bungee system, limit the amount the tank can be pulled up.
If the diver then levels the tank by lengthening the leash on the lower bolt snap at the bottom end of the tank the net result is a low mounted tank and a deeper overall profile. If the diver doesn't increase the length of the leash on the lower bolt snap, the result is a tank that angles downward relative to the torso, adding drag in the water in addition to having the same deeper profile.
But body type also comes into play. If the diver is...um...larger... and has a deeper profile anyway then there is little harm done. If the diver is really skinny and.or petite, then the DR system won't limit the upward movement as much as it would with a larger diver. If the diver is somewhere in between, then there's probably going to be a less than optimum result.
In short, how well it works really depends on the diver's build and how demanding they are in terms of having the tanks optimized for both low drag and minimum profile.
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From my perspective - out of the water - whether the tank is supported from the shoulder D ring on the harness by a bolt snap, quick link, ring and choked bolt snap on the tank, or by a bolt snap and a piece of 550 cord larks headed to the tank valve makes no difference - the tank is supported out of the water either way.
In the water however I get uniformly better results with the bolt snap and 550 cord, and it's a system that can be adjusted to give optimum results for anyone. Consequently, since there is no real upside for anyone, I don't recommend ring bungees or even just the bolt snap and quick link portions of that system to anyone.
It's probably worth noting that my Hollis Katana 2 came with a quick link and small bolt snap to connect the bungees to the shoulder D rings so they are easy to locate and loop over the tank valve. I removed them before I even bothered to adjust the harness. Like a ring bungee system, they potentially limit the ability of the bungee to lift the tank, and unlike a ring bungee they do not take the weight of the tank off the bungee. Once again a 550 paracord loop leave the bungee easy to find, without limiting upward movement of the tank, and a bolt snap and paracord loop around the tank valve keeps the weight of the tank from placing excessive strain bungee when out of the water - and it prevents any strain at all if you wait until you are in the water to loop the bungee over the tank valve.
