40 hp vs. 20 hp with booster?

So I am installing an irrigation system for a horse show. We need 350 gpm @ 100 psi. The driller I work with offered two options, a 40 hp or a 20 hp with vfd booster. My initial thought was the 40 hp because it's one less thing to go wrong but I am not sure. What do you guys think? Valve man I already called you about this project and a 4" CSV, maybe you remember?

I'd go for the 40 HP and a csv...a lot less to worry about.......whats the pumping water level out of curiosity? You know the 40 will have to be a 460 volt motor...the 20 could be 230..not sure if that's an issue.

I think we are about 50 to water and they were going to drill 100' casing with 30' of screen

Well it is going to take about 40 HP however you do it. So a 20 HP in the well with another 20 HP booster would work. But a single 40 HP in the well would be much simpler and easier to control. Then all you have to decide is if you are going to control it with a Cycle Stop Valve or a VFD. I am a little bit biased, but I could give you plenty of reasons why.