Homebrew PCBs

Anyone here etch with CuCl2 but only rely on air for regeneration ? Just 
wondering what other peoples experiences are with this etchant.

I'm using HCl + CuCl2 at S.G = 1.36 and etch speed appears to be about 
70% of fresh FeCl3 (S.G 1.4) at room temperature. The HCl concentration 
I'm running at is approximately 1N (or 40g/l HCl or 1 Moles/liter or 
4%). I found S.G of CuCl2 dramatically effects etch speed. e.g CuCl2 at 
S.G of 1.15 was about 10 times slower etch speed than at S.G of 1.35.
Commercially, CuCl2 etchant operates between S.G 1.35 ~ 1.45.

Adam