The SRAM OpenGlide cassette uses an aluminium holder that retains steel cogs and is a radical design that omits one tooth on every cog to aid smooth shifting. We experienced an intermittent problem with chain slippage but this vanished after about 70 miles of use. This may have been attributed to a quality control issue but the shifts have been both fast and positive ever since.
The choice of ratios - 11-23, 11-26 or 12-26 - is limited but biased towards the 'compact' chainset user. Combine the 11 tooth inner cassette sprocket with a 50-tooth chainring, and the competitive cyclist will get a much more useable top gear than the commonly fitted cassette that starts with a 12 tooth cog. While the SRAM cassette costs less than the Campagnolo equivalent, it costs £20 more than a Shimano Ultegra cassette that works perfectly with this gear system.