From their website shows that you can force 250 gpm thru it with 115 psi, that takes a lot of power. That is 13.25 acre inches per day. So would take a little over 9 days to put an inch on 120 acres. Thing has up to 2900 feet of 3 inch pipe, 3 inch pipe is kind of small for that much flow.

I think it would work best where you can split a field into 2 or 3 crops that have different times of year when they need water and run a lower gpm thru it. Like corn that is planted in April and soybeans planted in June. Corn would then need water in June and July and soybeans would need water in August and September. Add wheat to that mix and it would need water in April and May.