If z at the ending is more common I'm ok with that, no need to introduce even more confusion 
On the drive size issue Tim raised, I agree with you in general but having bought an SSD recently I also hate to see (any) space wasted. And because I prefer quality over smaller files sizes, (optional) compression seemed like a nice all round solution.

On the drive size issue Tim raised, I agree with you in general but having bought an SSD recently I also hate to see (any) space wasted. And because I prefer quality over smaller files sizes, (optional) compression seemed like a nice all round solution.