If it's a standard RBZ 3W, be aware it has a slight draw bias, and the stock shaft is 45 gr. and has above average torque at 4.5, and has a low kickpoint. All these encourage a higher launch and a right-to-left ball curve (for right-handers).
At a 6.7 HDCP, I assume you have fairly good clubhead speed. You might the RBZ Tour FW; it has a square face, and comes with heavier shafts. You might want to print out the specs for RBZ vs. RBZ Tour, and take them with you to the fitter.
I have the RBZ 3.HL (really a 4W) and the 7W after a fitting. I got lessons afterward from the pro and fitter, and he has got me going through the ball better, and I am now about 85 mph on my driver. The driver and irons have improved nicely, but I started hooking the RBZ family. If I play with an open stance, I get a straight or slight draw shot, aside from an occasional superhook miss.
So, on RBZ, make sure the shafts aren't too soft. On the R11, you can make adjustments, so you can fine tune it a bit.
Also, you might drop a line to Beachcomber. He's a better golfer like you with RBZ FWs, and maybe could speak to your game better than I can.