I'm not sure about the VT20, but Panasonic 2011+ plasma black level should be better than any LCD TV's. Including the 900-F. Add in the fact that there's no local dimming variance to worry about and yes, black performance on the nicer plasmas still beat even the latest LCDs. The only thing they lose out to are, obviously, OLEDs.
LG OLED65B7 | Yamaha v661 | Aperion 5.1 w/ SVS sub | PS4 Pro | Xbox One X | HTPC (i7-7700K, 1080 Ti, Define Nano S)
Pioneer 5020FD | Panasonic 46S30 | Hitachi P50V701