Bought a pair of these to replace the original 2-sided beaters that came with the double bass pedals years ago. Using these with e-drums and after using those heavy beaters for a long time, kicking with these felt like a breeze (though these have rubber, not felt), as if a weight had been lifted from the feet.
For playing very fast beats accurately, these work as the name implies: accurately. The light weight allows for very precise playing though wouldn't use these for heavy kicking, these aren't exactly made for that. Not enough weight and the light weight also isn't the best thing for drummers who use rebound a lot as the beaters lack inertia to bounce from the drum head. But that also means less work at keeping that inertia in check which caused endurance issues with heavier beaters.
The quality seems and feels good.