I will only settle for PBT now. Stock ABS keycaps are terrible in comparison. They're thin, shine fast, and feel slippery. I haven't tried double-shot ABS yet, so I can't speak much about their feel. However, from what I've read, they shine fast.
PBT has the right amount of texture. They have NEVER felt slippery to me. I have dry hands, so that may be a part of it. ABS tends to build up the oil from my hands on its surface. Also, from what I've read, PBT takes much, much longer to develop shine.
So, for these reasons, I will only settle for PBT sets. Double-shot PBT sets will be amazing...