Wow.. I guess I should request some additional features for SAI !!!!!
Seriously.. SAI needs:
1. custom brush including its spacing feature
2. More Layer Modes like in Photoshop
3. Customizable shape for Linework Layer.. e.g. Circle, Star, etc
4. More transformation tool like Deformation tool in photoshop
5. any kind of guide for perspective.. or perspective tool or something similar..
If SAI could have those features in the nearer future update... then I'll proudly say...
ALL HAIL SYSTEMAX !!! ^^