I can't answer your questions but I can attest to the Challengers longevity. I know several other people who have very old Challengers. Mine was under the deck with little exposure to elements. Until I replaced my well working Challenger 2.23 HPSF, this spring, with a Pentair VF, my Challenger held up very well over the years with near constant use 24/7, year round since 1986. I think the motor was replaced once (but maybe twice - seals replaced of course) since 1981, when pool was built. I think I replaced the wet end (impeller and pump basket) once since we moved into this house 1986; pool built in 1981. A lot of trash had gone through that pump, over the years, with impeller clogged up a few times. I can't attest to its efficiency but it surely did move the water well. There were several impeller clogs doing spring cleanup when I had to let the pool become an uncovered swamp over a few winters when I was away from home for a month or two around December Holidays. That didn't damage the impeller. Just needed a good clean out.
When I replaced the pump, this spring, I was hoping to use it as a trash pump but my model couldn't be converted to 120 volt so I purchased, at a good price, a new Challenger 3/4, that can be wired 120 v. For the price I got it a motor and seals only wouldn't have cost much less than the whole shebang. I haven't decided what to do with the old 2.23 HPSF, 220v Challanger.
The Challenger does have a good track record, but again, power usage efficiency may be an issue in high electric rate areas. Just guessing about that though.
BTW.... I have already noticed a decrease in electric bill, comparing to several years bills at this time of year. My Challenger was one speed and probably way oversized, especially with the undersized DE filter I replaced. It did, though, give enough flow to use two PoolSkims with one of the four returns closed off and the other narrowed down a pretty well. Challenger, of course, was running wide open the whole time at > 3 K rpm. Running the VF at about 20 gpm, or less, at ~ 200 watts, or less, ~ 15K-17K rpm (all determined by how dirty the filter is - speed/wattage go up to keep same flow, as filter starts getting dirty) (I replaced the under sized DE filter with a large Quad 80 and 2" pipes, at pumping station, and removed some unions and 90s, so much less restriction at station) gives enough flow to one Pool Skim, one 3/4" eyeball, one closed, and one restricted pretty well. Pool Skims need a lot of flow to get adequate venturi action. At that speed and flow there is plenty of flow to the Polaris booster pump without the VF speed increasing much to provide flow to the booster.
gg=alice
