Bucks - Bucks are the dimensional lumber which line doors and windows and allow attachment of the doors and windows. Beam Pocket - Beam pockets spread the force of the point loads for structural beams and allow for even support from posts or splines. SIPs are the best possible humidity control to allow long term aging of the frame. This reduces twisting and checking. The reduced labor and quicker close-in translates to reduced final cost on the structure.
Nothing insulates better than SIPs.
Often, gable ends are much more cost effective and easier to do in SIPs. Occasionally, a bump out or bay can be done with SIPs more easily. Certainly, floors, roofs, and dormers are best done in SIPs. SIPs are the only building product system which insulates in the same way as log systems, utilizing solid insulation with thermal mass, which makes them highly compatible with log building systems. Often, gable ends are much more cost effective and easier to do in SIPs.