The MacKissic machine I bought last fall does a good job shredding up hardwood and other leaves for composting. I don't have a lawn or own a lawnmower, so this machine fills in nicely. It kicks up a lot of dust, but it reduces the size of the leaf pile probably by 10X for the compost pile.
Not as great of the leaves are wet, it will still shred them but not as well and clogs occasionally. It's OK for occasional branch chipping but not ideal. Anything much larger than an inch or two I cut up and burn in the woodstove or firepit. I don't have much stuff like that so it's not a big limitation for me.
I think this is one of those no free lunch deals. A shredder makes a marginal chipper and a chipper makes a marginal leaf shredder. In my case, my property is small. If I were on land with a lot more stuff to deal with a larger tool would probably be in order.