I can't say I've noticed my TX taking any less wind than PCP's. When I shoot a comp I usually sit next to Martin Owens on the zero range because we car share and we usually check our zero and windage against each other. He shoots a Styer with 7.9's and we usually get around the same windage when we both take a shot at the same time.
Although having said that, the last comp I shot was Castle last Sunday - I missed 3 for wind, 1 I gave outside edge and thats where the pellet hit, the other I gave outside edge again and it split on the edge (not taking the target down). The other one, I gave a kill of wind and it sailed across the plate to the other side, others (with PCP's) had knocked it down giving the same windage as me... So who knows?
This was with my tin of die 19 pellets, which in my group tests did seem to take less wind (although not very scientific)