Hi, I have an old Wacom Bamboo with an active area in the size of A6 (small). I will upgrade to a new Wacom Intuos Pro. I just don't know which size to get; the medium (A5) or large (A4) size. I use it in Photoshop for retouching and recently started to paint and draw also. I have a 27 monitor. What would you say a medium or large? What are the pros and cons for each size? Thank you!