I know of 1 guy that used these and liked them. Everyone else just runs stock as far as I know in the DD2 class.

http://frixa.org/race-products

there are 2 compounds depending on ambient temperature. They have a disc also.

I would not recommend using the Frixa brake pads on a non-Frixa rotor.  While I prefer the Frixa brake setup over the steel VEN05, my experience was when I purchased both the Frixa rotor and the pads (never tried the Frixa pads on a non-Frixa rotor).  I think I recall someone trying Frixa pads on a non-Frixa rotor and it wasn’t good at all…

My last 4 karts were CRG’s with VEN05 brakes and I highly recommend you stick with OEM.  I have tried numerous times to save a few bucks and go with aftermarket and on several times they have disappointed me.  While some claim “OEM compound” I can’t say that they ever felt the exact same as OEM…

If you do go with aftermarket, I have had the best luck with the ones that Acceleration Karting sells.