I have both and they are great, the AAA is is not much bigger than a AAA batt and perfect for a pocket with pretty good output for locating keyholes, reading, etc..
The LS is the size of a CR123 batt. (maybe 1 inch. x 2 1/4)which some people don't like in thier pocket, but it puts out a
LOT more light.
It won't blind anyone like an E2 but I can read my tv guide from 30 feet away and it lights up the entire area under my carport.
I recommend you get 1 of each.