They get almost as big as C. aeneus. Here are my old ones during what I think was their final spawning. For reference, the box filter is almost 3 1/2" across the top and 3" across the bottom.
Am prob gonna get some Pandas now though (coz I like them and at the end of the day I can get them in my LFS whereas Pygmys I can't). I'm happy with it now I've decided