11" is the biggest you can go with stock 16" wheels. I'm sticking with 10", I think. I'll let you know more soon. I'll have a set of rotors to try by Friday. Many thanks to Ty for bending over backwards for us again. The rotors I'm getting are slotted, not drilled. The slots allow for extra grab on the pads, the rotors are hardened to withstand performance pads better. The slots are wider so that they don't fill up with debris from pads, but there are only 6 instead of 8, so surface area isn't a problem. The key design element is that the slots don't extend all the way to the edge of the rotor. For those with a physics or mechanical engineering background, you'll see the benefit of this. The rotors are less likely to crack, as the edge is thicker this way without slot intrusion. Baer rotors are also done this way, and I think Powerslot used to do this.
I'm not going with drilled rotors. Most cross-drilled rotors are intended for track use. The slots will give me better bite, and shed water better than stock rotors, the rotors are hardened, which goes well with my choice of pads, and they're made from precision blanks, like Baer, and unlike Powerslot. This helps prevent warpage, since I'm sticking with a stock 10" diameter. My NORMAL braking will probably not improve noticeably, but a hard bite or wet-weather braking will, and I won't have the brake dust problem.
I'll post more info when I get them, and after I talk to Ty again. He may be considering selling these suckers on his site, so I'll also post my price when I know it. All I know right now is they are more affordable than Powerslots, and MIGHT be a better product. If they get here in time, I'll be putting them on next weekend.