The RAR stock is not the stiffest, but seems to be fine where it counts. If a better stock will make it shoot better, then it will shoot REALLY well!
How much do you think a better stock will improve this one? 140 ELD-Ms and RL17.
Seems reasonably repeatable too.
Even factory stuff! (Hornady 140 ELD-M)
Or hunting bullets (140 Partition with RL16 @2770)