I have tried the above two clubs both R flex Asian spec. R11 FW is 15.5 degree and Diablo is 15 degree. It has a totally different feel.
The R11 FW can feel the heavy club head. The Callaway Diablo is light with a one piece feel, like holding a stick.
When hitting the ball, R11 FW can feel the club head is hard, just like a big stone hitting the ball. The Diablo has a soft feel without much vibration to the hand.
The ball flight for R11 is low and penetrating. Diablo has high trajectory. and easy launch.
I prefer the Diablo feel. But wonder what made the different in feel. Shaft flex, kick point, swing weight, material or the club head weight?
Hope anyone experience can provide some feedback or club fitter can give the spec of this two club using the same equipment for a comparison.