I recently got a 6040 as a size upgrade from a Proxxon MF70. I replaced the drivers with a Gecko 540 and used shielded cable. The pump seemed electrically noisy so I'm using the pump from my laser. I'm happy so far.

I'd say you should start using it and upgrade as you need to. Even the shoddy stepper drivers might be OK for a bit. You may well find that's the only bit that really needs replacing.