imatrix A/B — all-MiniLM-L6-v2 (cstr/all-MiniLM-L6-v2-GGUF), cos vs full-precision gold, n=5, calib=10
q8_0    imatrix=0  cos_vs_f16=0.999622     24.7MB  -> (A/B only)
q4_k    imatrix=0  cos_vs_f16=0.973741     19.4MB  -> (A/B only)
q4_k    imatrix=1  cos_vs_f16=0.974477     19.4MB  -> all-MiniLM-L6-v2-q4_k-imatrix.gguf
iq4_xs  imatrix=1  cos_vs_f16=0.978770     19.3MB  -> all-MiniLM-L6-v2-iq4_xs.gguf