As an experiment I loaded up my feeder and 2m big-wheel on HF tuned against a mains ground. It matched on 40m, 30m, 20m, 17m and 15m but it did not like 10m. I have still to try other bands. On 15m it was getting USA spots on the first transmission at 2W and on 40m it got 9 spots (all Europeans) in the first TX with no effort. It was receiving well on all the bands I tried and giving plenty of stations spots via WSPRnet. The feeder and 2m big-wheel, tuned with my LDG ATU, would allow me to WSPR on most HF bands. One night I shall try the 2m big-wheel and feeder on 472kHz, using a ferrite rod to resonate it and a 3C39 toroid to match it. It will be interesting to see how this compares with the earth-electrode "antenna".
UPDATE 1427z: I see my 10m WSPR has been spotted by FR1GZ (9724km) using the 500mW beacon and Par triband end-fed wire. Conditions on 10m are good.
UPDATE 1556z: LA9JO (2096km) spotted me on 7MHz, for my best WSPR DX, so far, on that band.