The Form 2’s new peel process and heating mechanism allow for a little more wiggle room with support usage (the new heating system makes the resin less viscous). However, this does not mean that support structures are not required for most pieces. We still recommend using supports for most items as the structures help promote resin flow and prevent initial compression from effecting the bases of your prints. Quoting our support site again:
“Flat surfaces with support structures print much more successfully at an angle of at least 10–20º. You will notice that if you use the automatic orientation in PreForm by highlighting your part and clicking “Orient Selected” it will usually position your piece at an angle. After each layer, the printer performs a “peel” process, which literally peels the layer off the PDMS surface of the resin tank. The forces involved can distort the extremely thin layer of a flat surface mounted on support structures. If a planar surface is oriented at an angle to the build platform, there is only a little overhang for each new layer. Furthermore, many thin-walled parts present significantly less area in any slice when printed at an angle.”
The full article on our website is here: http://formlabs.com/support/guide/prepare/model-orientation/
Hope this helps!