For my personal opinion about MT3, see: Why I dislike MT3 keycaps
I read you prefer cupped sculptured keycaps. Perhaps you should try out SA AF. They have very nice legends, are less aggressively cupped than MT3 and they are made out of an ABS+PBT mixture. SA AF keycaps are certainly not as textured like pure PBT is, but nonetheless they are less slippy than pure ABS. Moreover, they are very cheap on Aliexpress, so definitely worth a try.