I have noticed distance loss (significant distance loss) on heel shots. This occurs when the heavy weight is in the heel or the toe. But, for me, I've noticed more strikes on the heel when the heavy weight is in the heel.
Currently, I have the R1 set to 9.5*(upright), neutral weights and face plate at 2* open. This setup really has me striking the ball on the middle of the club face. Realizing that the R1 has an upright loft setting was really a breakthrough moment for me.
For those concerned about heel shots (and the resulting distance loss), I suggest you demo the R1 and see for yourself. My common miss is on the heel, and I was pretty concerned when I saw the ball seemingly drop out of the sky on heel strikes. But, I was able to make adjustments with the R1 to have me striking the ball away from the heel and pretty much dead center.
I know that I have said this before (many times) in the thread, but the adjustability of the R1 is really, really impressive. I have not been the biggest proponent of adjustable clubs, but the R1 has really opened my eyes to the possibilities that these clubs can provide.