Tall fescue will take be more drought restant. But, grows in clumps. KY bluegrass in my opinion looks better and once you get it established will be easy to maintain as well.
Have you thought about seeding it instead of sod? You don't have to water if you don't want to. The seed will establish better in the long run. Sod is grown in optimal conditions at the sod farm, regular fertilizing, watering, etc. If you don't keep up the routine it can stress out the sod. Also, if you don't install it and water it properly, you can get seams.
Good luck!!