I use diamond outdoor & indoor filter. The outdoor filter do have have backwash capability and I do monthly backwash & call diamond guy to take out the filter for full cleaning every 6 months. I have to tell you that even after monthly backwash, you'll be surprise to see the amount of dirt trapped during the 6 months full cleaning (manually take out and jet wash the filter). I think any water filter system can do a good job, so long as you do the proper maintenance. I don't really feel the water pressure is affected, even just before the full half yearly cleaning.