as per description from absolute black website
In order to get best results we recommend increasing cage return spring tension. New derailleurs are assembled with the spring in the mount that allows the most relaxed position of the spring. However there is another position on the cage which will increase that tension. It is a standard procedure, please navigate to point no.7 in the link. You may also ask your LBS to do it for you.
Basically i'd like to go 11-32 but realise this would use a longer cage and probably more susceptible to chain drop.
Anyone have any experience of running 1x10 or 1x11 with shimano non clutch mechs?