I just got a 24' Desert Spring. From my research Doughboy has been around for a long time and they seem to have a quality product. I like the look of the Desert Spring and it seems pretty substantial in terms of quality. The cost of my package was around 3100.00 which came with the Madrid liner (doesn't have the expandable bottom), no pool cove or Zap Zit or other chemicals but pretty much the rest of the stuff you listed. I got a cartridge filter but they also offered a sand option. Although you are looking at a bigger pool, it seems expensive as it was only $300 difference between a 21' and a 24'. I actually bought the pool last year on layaway so I'm sure prices went up since last year.

You might want to go to the Doughboy website and find another dealer in your area to get a price comparison.

Good luck!

Peter