I have a friend who used a ZeroFive flagpole antenna. He fed it with an Elecraft KAT500 (and KPA500 amplifier) and about 25 feet of LMR-600. I don't know exactly how he did his radials, but I know he had them. He has since moved and is still working on his new set-up.
I am using a ZeroFive 27-foot vertical (not a flagpole). I'm feeding it with a LDG AT-1000ProII and 50 feet of LMR-600. I have 16 30-foot verticals (and need more). I was previously using an Icom AH-4 mounted directly at the bottom of the antenna, but I'm planning to get an amplifier and the AH-4 can only handle about 120 watts. The jury is still out as to which set-up was better.
The thinking behind the LMR-600 is to reduce the feedline losses between the antenna matching unit and the non-resonant antenna.
My friend is a serious CW DXer and worked many countries with his set-up. I chase a little DX on SSB and RTTY and do a bit of RTTY contesting. I've been reasonably satisfied with the results given that I'm in a location where I can't put up a tower.
If you have questions, I'll pass along what I can.