My heating guy told me.........
This is, of course, when I owned instead of rented: He said that the longer the tank warranty the better built (and yes, more expensive) the tank would be.
My landlord replaced a 40 gallon no-name with a 30 gallon gas Whirlpool, and I have been most satisfied with it. I forget what the first hour recovery rate is, but it keeps up with my Maytag top-loader, my GE Nautilus dishwasher, and even a shower.
Tankless water heaters have an appeal, and advantages, but unless a person is building or extensively remodeling, the best answer is probably another tank of whatever fuel and size there is now. There are separate fiberglass blankets to add insulation, if one wants to do that.
Lawrence/Maytagbear