Depends on what you guys wanna shoot. I don't see Nex-3 as a limitation to me and it serves me well in getting pictures I want.

As for gear upgrades, I personally believe it's all about satisfaction. You feel boring and wanna upgrade, go for it. Not really related to skill, I have seen some rich people bought good gears but the pic.............. *ehem*

I have skill and Nex-3 just enough for me. My 2 cents.