S,
If you liked the 80's, you will like your IFCS...
With robots they no longer make sense to install.. They make the plumbing very complicated and harder to repair later.
They often are integrated into the pool operation so you can't just shut them off.
We don't recommend them... I would suggest you get a low voltage robot.. Like this..
If you do decide on an IFCS, make sure you still have 4 wall returns and that the ICFS is plumbed with a valve so that you can shut it off and still run the pool if something goes bad.
Most people that have pools with spillover spas, have an automation system that switches between the pool mode and the spa mode.. If you get automation, then you need to get the same brand of VS pump as the automation, to ensure they can talk to each other.
Why do you think that you will need two pumps???
Thanks,
Jim R.