I wonder... Since these systems seem to be highly problematical, how long have they been around? Any likelyhood they'll be much improved in the next few years, say?

I would hardly call SWG "highly problematical". They do have their quirks, which is unlikely to change. SWGs have been around for about 40 years. Several dramatic improvements were made about 20 years ago. Changes in the technology over the last five years have been very minor. It seems plausible that the required salt levels may come down in the next few years. The technology to support that exists, but it's adoption is by no means certain.

Salt cell generators for pools started over 30 years ago in Australia. Major improvements? Not likely. Possibly an incremental or two. Problematic? Hardly. Not understanding them does lead to issues. Are there BMWs and Yugos? You bet.

Scott

We sell chlorine generators which require a minimum of 50ppm of salt.
So they aren't SWGs anymore, more like FWGs

At this stage it's only in commercial range, but residential models will come out in the next couple of years, once they go through all the necessary approvals.

Pogo, SWGs aren't problematic at all, I would estimate that only around 1-5% of people actually have problems.