What kind of engine life can you expect out of a new engine by putting the wrong oil in it?

I work at a certain auto parts store. Not allowed to disclose for obvious reasons. An I'm no mechanic by any definition. I know you can expect to get less life out of the engine obviously. With that said, I just a customer tell me he's run conventional 10w-30 motor oil in his 2011 honda accord (which calls for 0w-20) since he bought the car. Hes now put over 50k miles on the car running the wrong oil. So what I'm asking is, what kind of life expectancy could a person expect by doing this?To me it seems he'd have already shot every bearing out of it by wearing out the pump. I know the two oils arent THAT different when theyre warm. But surely itd have a bigger hit on it in the colder months.Thoughts? via /r/cars http://ift.tt/2rQMvW4