In terms of lasting I think you are asking for how long would you be able to run all games maxed out. Truth is prolly not too long, but in terms of the components you've chosen it should last at least 5 years.
So when I go for a new build I try to make sure I have a 5 year warranty on those things I need to keep around, like the PSU, hard drives, SSDs, etc. The video cards will likely be the first upgrade down the road, so I like a 3 year warranty.
I agree, this build will be a beast for some time to come. I'd say maxing out games should not be a problem for two years.