AFAIK Amigakit are the only one that survive purely by selling Amiga products, and for all the others it is a sideline. Amigakit operate from an industrial park which saves costs and being based in one of the less expensive regions of the UK helps a fair bit no doubt.
Power Computing are still going but I think they exited the Amiga market about the time Amiga Active magazine closed.
I bought a quite few things from them over the years including a spare A1200 when they started selling them for £99.99.
