Let's compare our Flagpole Antenna, 20' and 28' versions with the Hy-gain AV-680 and Cushcraft R9:
The Red inner rings are 80M, blue 40M, green 20M, and orange 10M. You get the idea.
Look at the low angle in the OCFs and that extra punch. Yep, no radials needed!. Sure, you can use radials, of course, but not required for this performance! Likely not worth your time with very little meter movement until you get to 130 radials by our study.