It is difficult to answer this question. But in my opinion, bitcoin will last a long time ... Because bitcoin has been around since 2009 and survives until now with 2017 with a value of $ 70xx, so I think it will survive. It's much longer and it's hard to make the bitcoin go bankrupt.
Difficult, that's why OP created pool with two options,I don't know and we will see, like there is the difference in this two voting options. We didn't know when will bitcoj appear, how can we know when will bitcoin disappear, maybe not in our lifetimes, like in next 50 years bitcoin will be here for sure.
I believe that just some new and more powerful technology can destroy bitcoin, we had many topics here about possible bitcoin ends, and from all comments, possibilities this one sounds most possible to me.