I only ran mine on the dyno. They are super quiet and you can barely tell they are on with all 3 running at the same time.
I got the idea for my fuel system from the guys on theturboforums.com . A whole bunch of guys have tested this set up with great results and no problems at all up to 1400 EFI Boosted HP using 3 of them. The Walbro GSL392's are great for multiple pump set ups, reason being is they flow MEGA Fuel are quiet, will act as a DEAD HEAD so no fuel will go back to your tank if you turn them on at different times and they will also LIFT Fuel so that will open up where you can mount them. Also they are inexpensive at $100.00 Each. One of them will support 600 Boosted EFI HP. Yes they can be used on a Carb set up too!