I replaced a 3-month old set of Elixirs with a new set of EB coated strings last week. The Elixirs were getting a bit hairy and starting to tarnish in places, but probably still had a few weeks left in them.
The EBs are not as smooth feeling as the Elixirs; people who don't like the slick feel of Elixirs should like the EBs better. They "squeak" like regular nickels at first, too, but after a week they have lost the initial roughness and feel smoother. Or maybe I've just gotten used to them. Still not as smooth as Elixirs though.
To my ears, the EBs are notably less bright/middy than the old Elixirs. They almost sound somewhat scooped in comparison. (I was changing one string at a time and could tell the difference right away as I tuned each string to pitch.)
On my short-scale Birdsong I find the E-string on the EBs has less definition; almost muddy on the first few frets. I would guess they'd do better on a long-scale bass, but for this reason (and the relatively scooped tone) I won't be using them again on the Birdsong. YMMV, as always.