Samsung 840 EVO and 840 PRO SSD differences and comparison

I am about to buy new hard disk for my laptop, I have been considering various option. I have also option to upgrade to 240 GB SSD . I am told that only buy reputed brand like Intel , Samsung or Crucial and stay away from others. So after looking online, I can find two hard drives which I have shortlisted from Samsung, one is
Samsung 840 EVO series and other is Samsung 840 PRO series. On online store, both disk comes with 3 years limited manufacturer warranty and have almost same specifications. But Pro series is about 20% costlier than EVO series.

Before buying it, I need to know what is exact difference and why PRO series is costlier than EVO series ?

I think Pro series is made of a material which last longer than EVO series but even for EVO series, its 19 years of lifespan so I think you can even by evo seris without worry.

Ok, so you mean I can buy EVO too, that is also fine ?

But I was searching about it and found that EVO SSD by samsung develop problems of being slow and samsung is working on its fix. Should I wait or buy EVO drive now ?