I have bought the Ghost putter and the R9 280 driver. I bought them because I have little else to do with my credits, were I to have invested new monies into WGT I wouldn't have bothered on the grounds of their ridiculous cost.
The new driver according to my eyesight appeared to have the same meter speed as the R9 Tri, at least that's what it looked like in the Pro Shop graphic. On playing with it, it most certainly does not have the same meter speed. 80% of my drives were hit early during my first round with it. Most definitely a slower meter and it has to be said a slightly more forgiving club than the Tri.
The Ghost putter has a much faster meter than the Rossa, something I am delighted with. Recent weeks has seen my putting deteriorate, too many putts hit early. The Ghost on first usage has proven to be an excellent putter once you are tuned in with the meter speed.
I would say both clubs are worth purchasing if you have a bank of credits or simply don't mind being ripped off. If you don't fall into either of those categories, I wouldn't bother. Neither club is going to significantly improve your game.