Advantages of PETG filament?
PETG is great stuff to work with. It is stronger than ABS also. It prints slower than ABS and PLA. The formulas vary quite a bit from vendor to vendor. I have used 3 brands, and each of their properties vary.
From my experience you do have to be careful with moisture. You'll be able to tell you have moisture in your filament if you start hearing a slight hissing and popping and an increased number of structural zits on the object. Moisture will also increase the problem listed in Mark's post below regarding the accumulation of filament on the nozzle.
I absolutely agree with you on all points, @Asa. However, be careful about making subjective recommendations about products, as that is generally frowned upon in the Stack Exchange community. In this case, you could try to describe the difference between different kinds of PETG based on their properties rather than simply saying that one is "better and cheaper" - if you can! (Also, adding a reference that says the subjective opinions for you could help argue in such cases.)
Thanks for comment and I will make shure I put more substantive information. In my replies.