Recently we devloped mdf based art board and pine wood based gesso panel for acrylic and oil painting.
We at Snoogg.com do not see any disadvantage comparing canvas based painting board but we see number of advantage . These are
Creator choice of grain

Produce in multiple color even in small quantity
These boards never turn to loose 
Manage number of customization 

Rounded edge look much better than square one.
The biggest disadvantage we see these board are bulky and can be produced in Max size of 16 inch.
One can view these items at snoogg.com