I'm not as good as you Andy....but I tried a Callaway FT-i and although it seemed quite straight it didn't seem to hit the ball as nicely as my G5 or FT-3. It could simply be because it's hard to feel you've "middled one" with one of these square beasts. i.i.r.c. the Callaway had a tad longer shaft but certainly didn't give me any extra distance.
I say if we/I can find something comfy that goes a decent distance for our standard/swing (in my case 230-250 with 90 mph) and pretty straight, maybe best to find other areas to work on.