In short....
Pillar bedding gives you the assurance of more stable bedding system.
Wood will compress and over time it will move. Wood has the tendency to soak up oil, solvent and water etc. etc. Coating the wood through a wood finish or epoxy will help prevent the wood from soaking up liquids and dimensionally changing. Wood fibers are easily damaged.
Laminated woods tend to absorb a large percentage of the bonding agent (glues) during the lamination process (high pressure and absorption). Consequently they are harder and less likely to compress or absorb liquids/moisture like a standard wood stock.
Steel pillars matched in material type to the screws will ensure screw tension is not affected by expansion or contraction caused by changes in temperature! Penalty is weight. Aluminunum keeps the weight down but will vary screw tension with temperature changes.
Fiberglass pillars are also being used and apparently (I haven't checked this out) have very similar expansion coefficients to steel. They also do not tend to come loose.
Poured pillars are easy to do but are not as consistent as solid steel or aluminum.
Since this kind of work isn't too complicated, why not try bedding first and once you are comfortable with the pillar idea and you feel there is room for improvement, add the pillars later. Brownells sells pillars and we can order them in for you if you like or you can order them directly. I machine mine.
Hope that helps.