I've had several TRs (great amps!), and they do sound very good with Greenbacks.
TRs are bright amps with a lot of upper midrange, and the V-30s are pretty bright speakers with gobs of upper midrange, so the combination tends to get somewhat ice-picky. Also TRs sound better with open or semi-open backed cabs than they do with closed-back cabs. I will say, though, that I did a lot of recording with the Onyxes I had and a closed back Bogner OS 2x12. Sounded pretty bad in the room, but great through a 57. So there's that.
The best cab I ever used for recording a Two-Rock was a vintage late 60s/early 70s Marshall 4x12 with the original Greenbacks. It was amazing sounding. But I also thought that both my Onyx Sigs and Custom Reverb Sigs matched up very well with Mesa Black Shadow 90s (basically Celestion 80s tweaked for Mesa). Oddly enough, I liked these combinations better for my music than the matching TR 212 with TR65 speakers, though that was also a nice cab with the amps for certain styles, just a little less "rock & roll."