I have few programmer for CAS. (UPA-S, VVDI, SMOK J-TAG, XPROG, ETL, MRppad)
I have programmed many CASs and I recommend MRppad.
X-prog, SMOK J-TAG not safe.
UPA-S - unstable.
ETL - it's safe but time-consuming (need desolder mcu)
VVDI is ok but sometimes he likes p-flash damage when you crack mcu.
But this is not big problem.
MRppad - for me is the Best, no need desolder any components!
Safe and stable.