It's looking good to me. It's definitely getting enough sun if it's that red.
You can leave it in the pot if you wish, but it might be even happier in a larger pot (and look a bit better). You can repot into an Irish moss peat / perlite mix and split it with scissors if you wish. Maybe put the spares on ebay?
It's not a catesbaei - it's a Dutch tissue cultured hybrid which is very common in garden centres. It definitely has purpurea and minor in it, but possibly something else.