I actually used to frequent Waffle House until that night in Memphis.
Waffle House is like a crappier Denny's, IMO. If there was a hierarchy of greasy spoons, I'd say it goes like this: your local run-down greasy spoon-->Waffle House-->Denny's-->your local decent greasy spoon-->IHOP or Bickford's-->your local "hip" diner.
I like Steak n' Shake, but they're kinda pricey.