With any of the larger rear bars, and stiffer coilovers...I would think you'll have a tendency toward oversteer. Which is FUN...but not as fast as it could be for open lapping.
I used to drive at the limit, lots of tailsliding...and it was relatively quick, but not consistent AT ALL.
I have since learned to appreciate consistency, "the racing line", a more balanced suspension setup...and have learned that bigger/stiffer is NOT always better.
Anyway, enough of my ranting...
I'm thinking that your setup will be similar to mine, and a 1" F/R stagger would be beneficial...for both wheels and tires.
I plan on a 255 F and 275 R setup with my next set of wheels, and then I'll be happy
245s all around will probably feel good, but try it someday with your stock rear swaybar and see the difference in balance, you'll be amazed.
- Brian