We have just installed the first 2010 crop of modular sedum trays, in the easier to install 0.5m2 size.
They are easy to carry, click into place, and finish. Over 100m2 was installed within one day by a gang of three men.
The sedum will become settled and established much faster than by using a sedum blanket onto loose substrate, since its root system is 9 months old and fully established.