Syn: it works fine, but it is noisy, it is in an adjacent closet to the music room, and there is nasty electrical snap when it cycles, even with the extra relay Kuzma provided- the only way i got rid of the electrical snap was to plug it into a big 240 volt isolation transformer! I did reach out to Scott M re the upgraded pump, which has a bigger tank, and arguably requires fewer duty cycles, but i thought if I could go 'pump less' there might be joy! When i move, i could relocate the pump to the outhouse or whatever, but I'm trying to simplify my life.
btw, just got the lamm L2 back in the system, and it is kicking some serious ass with the Allnic H3000, which is now further along in its break in cycle.
Still be curious if anybody did a direct compare between the Airline and 4Point for sonics.