The vac is mainly to get up leaves from driveway without picking up gravel & flower bed without picking up wood mulch. .
As the wizard said, not gonna work well, especially if they are wet.
I had a Craftsman leaf blower you could convert to a vac mulcher, it stunk.
I had an old TroyBilt monster (47282) that would shred up to 3-4", but as a hosed vacuum it stunk, you could pick up a random leaf here or there, but not a pile, without clogging. I could occasionally rake light dry leaves into a chute, and it could **** them up, for a while. As a walk behind vacuum it was better, but again, a light coating of leaves, not a fall weekend in the Midwest, where you rake a 2' high pile to the curb line for the city to pick up.
Now moved on to a Tazz, same story, but they at least tell you it's only for sucking up random leaves, not digesting a pile.
Again, mulch was hard to stop from flying, gravel a little easier, but once you start getting a mat, or wet leaves, I've had no luck.