I have both these amp for a couple of years. I was just wondering if I should upgrade? To be honest I only use them once in a while. I see a crop of newer amps from various companies for 120 and lower. I've looked at recents good review of the newer amps such as Fiio E7, E11 and also Soundmagic A10(i own the soundmagic L50 and love them). Thoughts? Very grateful for a reply.