I'm interested to hear how you get on with the PETG. I've never had any issues with acrylic but with the distinct lack of clear acrylic tubing in the size I need for my fittings I'm having to order direct from the maker anyway so I have either option now. I was put off the idea of PETG by a few things I've read but not seen first hand results yet.
I know what you mean. I read all sorts about water permeation and it reacting over time with UV rays. However it is the same substance as most drinks bottles and they're relatively robust. Personally I think a lot of stories about PETG are over exaggerating to be scaremongering people