I have a tikka T3x CTR that I purchased a Manner's T6A and when I installed it sans bedding/pillars my groups opened up about .25 moa compared to the plastic stock it came with. I sent it out to a gunsmith and had custom pillars made and had it bedded, and the groups shrank by about .5 moa on average. Your experience may vary, but if you didn't go with the mini chassis, I would definitely recommend pillar bedding. The gunsmith also machined a custom recoil lug since the one that the Manner's stock came with was undersized.
Custom Pillars
Custom recoil lug + bedding
Finished rifle