NAS ? What is the best option

I know that this list is not connected with any hardware vendor but I see that every couple days someone cries here .... NAS problems... I use Mikrotik and I'm not satisfied (duplicated packets, does not support POD correctly , etc) Also, yesterday I see that Cisco can be pain in the a*** too :) So, dear friends... What is the best solution for ISP (PPPoE)?