Before getting my Zeons, I was quite interested in making the 32" size fit because I really wanted more aggressive tread on the tires that I'd only be using once or twice a year (go big or go home right?). After realizing that the big problem would be the spare fitting underneath I ended up with the 285/60/18 LTZ (31.5") - a great choice as everyone here is using them and they are a proven tire for our Sports.
I am very happy with my purchase, though I have realized that perhaps there was another option. Get the more aggressive 32"s for all four corners and just use the 31.5" as the spare. It might have a little limp getting home, but probably stay fairly capable. I may try this option when I need new tires in, oh, 15 years. I'm sure there will be plenty more options by then though.
Just my thoughts for someone who might want to try it.