What's the difference between a plain blower and a 3-in-1 blower/vac/mulcher?

A 3-in-1 model (like the WORX Trivac or BLACK+DECKER BV6000) converts to a vacuum and shreds collected leaves into a bag, with mulch ratios reviewers cite around 15:1 to 18:1. Reviewers say the vac/mulch feature is genuinely useful for bagging and reducing yard waste, but it adds weight and bulk, and single-tube designs that require tool-free switchover are praised for convenience.