I bought these and similar sets of round Irwin bits as the first bits that came with my first router so I'm comparing they not with as, but the result and the price were satisfied. I have used all three sizes for the project I bought them for and have had no issues with their cutting ability (just me) and have been pleased with the cleanliness of the cuts. It's a 1/4" shank (which I should have visited and checked before buying as it's not on Revain's list), but I haven't noticed any vibration or other issues that I've found while researching my read purchases. I liked the sets as much as any of these large sets but am happy with the quality of the bits I received and the sizes much more convenient.