Thanks for this info. I have a 24' AG (13,500 gallon) pool and found this information very helpful.
I went the same route that you did badutahboy except for the filter size. Instead I got the Waterway 19" sand filter with the 1HP 2 speed pump from poolsupplies.com.
Originally I was going to do the 22" filter but decided to go with the 19"er to save a little bit of cash. I am usually the type of person that would have jumped on the 22"er but right now cash is tight, this was an unexpected expense, and most of all the pool sees a VERY light bather load. I don't think the 19" tank will be an issue whatsoever.
I do hate that I had to decide quickly on the system I needed since my pool has turned swampy very fast. It looked great beforehand until the Pentair Sand Dollar tank split (BTW thanks Pentair for standing behind your product! [/sarcasm] [/end rant]) then it was downhill from there.
I had my heart set on the Hayward S180T92S which includes an 18" Tank and 1 HP single speed Power-Flo Matrix Pump. Although the Waterway's price along with the 2 speed motor won the inner-struggle I had on making this decision

. In the long run I know the 2 speed motor will be best anyway.
So badutahboy are you expecting delivery soon? They informed me that they have to ship the motor from Waterway in CA so it would probably take longer to receive. Hopefully I receive the items in a reasonable (a week or so) amount of time.
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