Project X Flighted on Tour

I've noticed many guys on Tour play Project X shafts but it seems there are hardly any, if any, that play the Project X Flighted. Is there a reason for this? It seems that a technology such as this would be very well welcomed to guys on Tour.

Love my Project X 6.0 flighted....money!!!!!!!

I think they're good too, but how many guys play them on tour? Doesn't seem like many, if any, play them.