Like everything else, it'll take a minute to get used to. Once you are used to it, you won't think twice about it.
I'll personally miss:
Carrying around a 35 pound black box everywhere.
Stowing that heavy case in the cockpit.
Picking up my charts after turbulence spills them around the flight deck.
Searching for that "missing 10-7 page"
Doing that revision that's 2 inches thick on my flight from LAX-MCI and not finishing.
Etc