I personally believe character and attitude are way more important than the economic factors like a high-income job. You have to ask yourself this question "if they both have high paying stable jobs, why are the looking to rent in the first place?" The answers to that question are they might have screwed credit, and are stupid with their money, and are generally irresponsible people.

Here is a tip for what it is worth. I always ask about where they are living now, and why they are moving. I usually work this into the conversation as I am showing them a place. If I hear a bunch of complaints and talk about how irresponsible their current landlord is, I give these people a pass no matter how good they look. These are the kind of people who are going to give you nothing but problems and headaches.