GPM - What is necessary?

Hello-
I'm going through new construction and will have a 4 bathroom house when done. Currently there are two adults and one small child, but hopefully that will grow over time.

I'm thinking of putting in an AP802 with the AP810-2 cartridge. At 45-60 gpm, this seems like it would be sufficient without any reduction in water pressure. Ideally, I'd like to use the AP815-2 cartridge, but it drops the gpm to 10. What gpm is necessary in this size of a house?

Should I use the AP815-2 and run two in parallel? Does that even make sense or is it total overkill.

We will also have a AP-DWS1000 at the kitchen sink. I've had one for 3 years and have been very happy.

thanks

Ideally, I would have a backwashing valve with a multi-media tank. These will provide excellent flow rate and the self-cleaning apsect will provide years of trouble-free service.

But first, can you post your precise water conditions. We might be able to better recommend serious equipment according to your exact demands and desires.

Andy Christensen, CWS