There are multi-purpose shredders available but I'm not sure if specific product recommendations are allowed on this site... even so there are few things to consider.
First of all, you should think about how often you are going to use it and how much material you would like to shred.
Second thing would be to choose from electric or petrol shredders. I'd recommend petrol because you'll be able to move shredder more easily and probably it will have more power than electric one.
If you want to put things like leaves or bulkier softer materials, consider getting a shredder with larger filling funnel because some have openings that can accept only branches of certain diameter.
I don't think lawn mower would be suitable for shredding anything other than leaves and softer waste. Smaller dried branches can be shredder with lawn mower but thicker ones could be a problem and could cause even damage. Biggest problem when using lawn mower for this purpose could be that material you want to shred is 'escaping' underneath the mower. There is also an issue with smaller volume of the bag for collecting clippings, so you might empty it more often.
Regarding durability, I think that electric shredders could overheat more easily so you might have to make breakes. The only real problem I had on my shredder was with rubber covering the filling funnel (which prevents stuff to be trown back at you) which was warn out pretty quickly.