Corel Photo-Paint has the BEST method for brush sizing I've ever seen. Instead of pressing a key (L & R arrow in AR or [ & ] in Photoshop and Painter), you simply press the Shift key, wherever you are on the canvas, and drag up or down to size the brush.
1. You NEVER have to move the pen away from the area of the screen you're painting on.
2. Since you don't have to move away, you size up/down the brush and see on screen against your artwork how big or small your brush is going to be.
3. There is never that delay in the key response (I set my keystroke responses in Control Panel to the fastest, and yet there is a delay depressing the L or R arrows or the square brackets.
4. Whether you're left handed or right handed, the shift key works fine. I'm right handed, so I find it rather annoying to cross over the keyboard with my left hand to reach for the arrows. Ergonomically it is uncomfortable.
I promise you, once you use that method of sizing brushes, you'll wonder how it is that not all paint/masking software use that system.
So how about it Rage Team?