I have a new domestic well that is 205’ with static water level at 56’ (drilled and measured in Sep after 2 years of drought). It is a 6” well casing with 4” PVC liner with 40 3/4” perfs from 165’ to 205’ sitting in mostly gray shale. The bail test indicates 6gpm. I’m building a residence that is under 2500 sq ft with just two adults. We will have a small garden and possibly some yard watering in the summer though the area is pretty shady with many trees and a creek nearby. We are in rainy Western Washington State. I have two very different estimates on pump size. One company suggests a Goulds 1hp 10gpm 12 stage (10GS10). The installer thinks the static level allows for a bigger pump which will somehow be more efficient as its gpm start at 10 but tapers down to 6gpm as the water level drops. The other installer suggests a Flint & Walling 1/2 hp 5gpm 15 (4F05S05) stage and says it will operate at the best efficiency and not overdraw the well. Can any of you offer opinions/advice as to which idea is more sound? Thanks for your help.

How deep will the pump be located? If you overdraw the well, you will be pumping air and that will destroy the bearings and seals in short order, since they are water lubricated.

At 195'. With the 1hp a low-water shut-off has been suggested.

A 1 H.P. pump will be oversized assuming your home isn't a tremendous amount higher than the well.
The Flint + Walling pump will be fine.

The house is not more than 5' above the well head and is about 150' away with another 70' to the fixtures at opposite end of the house. There's some real differences of opinion on this as I ask around. I would like the pump to be properly sized and run at its most efficient state most of the time. Some have suggested that, with the 1/2hp 5gpm, if I was watering my lawn or garden (neither of which will be very large) I wouldn't have water for the house at the same time.

If the pressure tank is properly sized, you will have enough water to use in the house and in the yard at the same time.

There are many things to consider when installing a new submersible well pump system as its a major investment as well as timely and you only want to do this about every 25 years if you choose the correct system?? You want your gpm test done in summer at your lowest level times because as you said rainy western Washington it's easy to be fooled by the well log if the test was performed in fall,winter even spring? Have you thought about a variable speed constant pressure system that comes with all pump protection necessary and there's no fluctuations in water pressure ! Almost as if being on city water without the chemicals added??