Microstudio always has been able to use CDRW's as so does Karaoke Home Producer.
I use CDRW's to do my initial run with Karaoke Home Producer. I prefer to play them on my large screen T.V. to check for any changes, typos, color combinations(always look different than on the p.c.)etc, and when I have it as I want it, then I burn to a CDR.
Only limitations I've seen is 10X max burning speed, and some players won't play them, but mine will, so that's not a problem.
Saves a lot of coasters.
George