As Bartacus says, the are both easy to bend.
The whole discussion behind which is easier to shape acrylic vs PETG is somewhat true but also a little moot depending on available tools. Both are ridiculously easy to bend. The only difference is that Acrylic needs a higher temperature. If you have a way to control temperature, it would be just as fast as PETG.
Of the two, I will always choose Acrylic. Simply because of the clear effect it provides. It also allows almost any coolant whereas PETG limits you to ONLY non-based glycose.
Acrylic
Pro
* Clearer crystal translucency
* Compatible with almost all coolants
* Doesn't cloud
* Handles higher temp (moot point but still valid)
* Smoother feel and more scratch resistant than PETG
Con
* Less brittle (but does not mean fragile)
* Higher cost
* Harder to cut and burr ends/edges
PETG
Pro
* Easier to work with
* Less brittle
* Cheaper
Con
* Coolant limitations
* Clouds
* Extremely easy to scratch (so screw type fittings watch out)
* Lower temp for warping
* No as good effect under UV lighting
Coming from experience. I will never trust PETG in my loop again. Simply because of an issue I had with 1 rotary. Paint flaked and broke off in fragments contaminating my loop and thus leading to a block at the CPU. It took approx 2 hours for one of the tubes to heat up and warp inside one fitting leading to a huge leak.
Pretty much like this. Allowing the coolant to flow wonderfully out of my loop and into mycase