I don't have any experience with the cinch buckles, but I have to put in another vote for buying stuff from Dutch. I HATE to pay for shipping, but his prices are hard to beat and the shipping is completely fair. As a bonus, the service and quality is top notch.
If you decide to use descender rings, here are the ones I ordered from Amazon.
http://www.amazon.com/Omega-Pacific-...escender+rings
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