First of all, I would say go to Edmonton for the simple fact that you don't know how to spell Petawawa and your mail would never find you.
However, I will say this:
I have served in both units and luckily I left 1 CER for 2 CER. It was like night and day between the two units. This was in the early 90's and 1 CER was in Chilliwack away from the rest of the Brigade. Chilliwack was nice, but the job sucked big time. Sitting around stores, cleaning tools, sharpening shovels, painted hammers, etc. Went to Pet and boom, the rest of the brigade was there so we were training, training, training. Nothing better if you ask me although there are enough lazy pers who think otherwise.
As I can't speak for the state of 1 CER nowadays however, I would say that it is pretty close to 2 CER in that they are swamped with tasks and tours and that they find themselves doing 10 things half-assed instead of 5 things right.
As a Sapper, you are like a prick in that you will go where you're shoved so don't worry about which unit is better or not. Each unit has it's own pro's and cons for sure.
People who are in Pet, like Pet. People who are in Edmonton, like Edmonton. And then there is me, I am in Gagetown and hate it!!!!! hahaha
Whatever choice you make will be a good one.
CHIMO!!!!!