CannonCaps: ~1.4mm thickness. PBT plastic. Less textured than NicePBT. Dye sub. Cross-shaped stem (+)
** CannonCaps CXA: ~1.85mm thickness. More textured than CannonCaps PBT keys, similar texture to NicePBT (but still different). ABS + PBT plastic mix. doubleshot. flower-shaped stem
NicePBT: ~1.7mm thickness. PBT plastic. More textured than CannonCaps. Dye sub and reverse dye sub. Flower-shaped stem on newer sets.
Hope that helps 