Not sure how to answer that. It could be that the R1 would fit under the OEM wheels with spacers - you need spacers with the Alcons as well with the OEM wheels.
Don't worry about it. I'm actually not that attached to the OEM's . But Honestly I'm leaning towards the Alcon's. I'm just not a fan of their finish. For the price they could look a little better. The red looks good, but at least paint your company name so it stands out.
Also another question, would all the factory sensors still work with the change to Alcon's or another BBK? I'm talking about the brake pad wear sensors and other miscellany??