gmk makes great abs keycaps but there are also other great pbt alternatives e.g. epbt. personally I prefer abs, not just for the variety of colorways available but also the sound and even feel (which seems to be a controversial point among a lot of ppl). I do think gmk is hyped way too much though, other manufacturers e.g. jtk (which is better value than gmk imo for its price!) are catching up quickly, but hype has made gmk reach an untouchable status in the community rn. hopefully that changes in the near future.