I'm another convert to the Stenner pump. I replaced my liquidator that has been in service for three years. It did the job but we are going to be gone for six weeks at a time twice this year and the liquidator does not hold enough chlorine to last that long.
I started the stenner up last Friday, May 1 and it is set-up to run anytime the main pump runs - currently 9 hours per day. The Stenner is a model 45MPH10 and I started with a flow setting of 1.0. I've tested the chlorine three times per day since starting up and every test has been either 3.5 or 4.0 ppm which is exactly what I wanted. Guess I got lucky.
The clicking sound that has been discussed a lot is not a problem for me. I can't hear it unless I'm standing close to the pump. So far I'm very pleased with the installation and the performance. The storage tank holds 25 gallons of 10.5% chlorine so that should be more than enough to last 2 months.