So was it worth it or does it add grief in trying to roll things in and out?
Only problem I had was trying to push a non-running, 3500+ lb. TransAm in the shop. The (gravel) pad in front of the shop is slightly uphill too, so that added to the problem. It was just my wife and I trying to do this, so, that didn't help. I just had to get a running start at it.
I could imagine it might be a problem if you were rolling something heavy in on small casters, i.e. engine on a stand, etc. But stuff like that stays IN my shop, so I have never had a problem.
I could imagine a sloped pocket like the guy above said might be a little better. But, at the same time wouldn't have as much positive rain protection, albeit probably works just as well.