Personally I own the m40 it shoots 420fps out og the box, the problem is there was a defect in the first few batches where the bolt assembly would shear of under 100 rounds as mine did. The good new is the replacment is free through vfc in co-op with your retailer.
It can be upgraded as mentioned in the video with the listed parts some minor sanding and some shims. Personally i would go with the Ca M24 platform, its my go to. With the proper ugrades and time it will be the most acurate bolt you will own.