Product review (4 stars): Filters and housings are good quality. Manufacturer should provide more guidance to help ...
Look at the mix of sediment in your main water filter before selecting your spin down pre-filter size.
 60 grit catches all the flakes of iron, sand granules, etc.
 if lots  of sand in your water, use their filter with sand collection space. If lots of fines and your main filter clogs too fast, use 100 grit.
 250 and 500 grit are prone to fast clogging if your water has lots of fines.

If you have a lot of fines, your spin down may not flush clean. You may need to remove and hand rinse the filter. May want to buy a second insert of the size you use if this happens regularly - shortens time the water has to be off.

Major rain storms can flush lots of particulates into the aquifer. Check your spin down filter after heavy rains until you learn how your aquifer behaves.

For the first few months after installation, inspect your spin down every week to learn how quickly sediment builds up. Depending on water quality, flushing may be needed every few days or every few weeks.

Consider adding a 1/2 NPT to garden hose adapter to the flush valve. Buy a 3ft extension hose to leave attached, and leave a 5 gallon Homer bucket nearby. Found I was more likely to flush the filter regularly if everything was ready to go.

Filters and housings are good quality. Manufacturer should provide more guidance to help customers select the right filter. I had to buy multiple sizes of filter inserts to figure this out. Could have saved $60 if pictures and guides were available.