PBT (polybutylene terephthalate) keycaps are often preferred by keyboard enthusiasts for several reasons:

1. Durability: PBT is a high-quality plastic that is resistant to wear and tear, making PBT keycaps more durable than ABS (acrylonitrile butadiene styrene) keycaps, which are more prone to shine and yellowing over time.
2. Texture: PBT keycaps have a slightly rougher texture compared to ABS keycaps, which many people find more pleasant to type on.
3. Sound: PBT keycaps produce a deeper and more satisfying sound when typing, which can enhance the typing experience.
4. Appearance: PBT keycaps can have a more vibrant and long-lasting color compared to ABS keycaps, which can fade over time.

Overall, PBT keycaps are a popular choice for those who want a high-quality and long-lasting keyboard. However, they can be more expensive than ABS keycaps, and some people may not notice a significant difference in their typing experience.