i feel that arm routine doesnt matter for shit if you just dont have the genetics for big arms. you could do every excercise, all different rep ranges, drop sets, etc ...but if your arm genetics suck, you wont build big arms no matter what.
if your natty and been training for a good 5 years, then your arms arent gonna grow anymore (esp if your past your mid 20's). and even if you juice and your arm genetics suck, you arms will barely grow, if at all,....just look at Big Dan Hill or Kamali. All the Slin and GH in the world couldnt help those guys break 18in arms.