On two Easter APUG get together (UK) a few of us tested some meters, and we found the readings to be remarkably similar, not even 1/3 of a stop different, that was Gossen, Sekonick, Pentax & Minolta.

My own meters (UK) a Luna Pro SBC used with the incident light cone cone and as Pentax Spotmeter V, or capital Spot meter, and this year a Minolta gave the same reading, as did the CDS meter of my Yashicamat 124. My DSLR amtched as well