Andy,
I have a Bosch 2200HP - its a chipper not a shredder so it is useless with
leaves and thin stalks - it throws them out untouched.
At the moment I shred my leaves with an electric blower/sucker shredder.
But is slow work.

A cheap Bosch shredder would shred leaves but for leaves you need a shredder
with a hopper feed - these are not that common.

I have a fair few prunings from bushes to get rid of and the Bosch
2200HP looks ideal for this. However I also have to deal with what
starts out as something like 4 cubic metres of oak leaves every year.