When this is available, I quite fancy one. My transverter produces about 10-12W of WSPR on this band. It would be good to try the QDX-M next winter, on 630m, if available. I think the output would be about 5W on the QDX-M.
In the end I located my antenna current meter but it was broken and soldering the toroid on again was very hard. Still not on TX.