The doser is good and it will give you peace of mind. My Ritmo and water pump needed expensive repairs after using Wickes and not flushing out.
But I did continue using accelerator mainly an Irish one what didn’t ha the Chloride free additive in.
I took the pipe off the mixing chamber, wacked up the float to maximum and took out the mixing shaft then ran it for a couple of minutes on speed 10. Not had a problem for 4 years after the repair and I used Accelerator all year round except for overnighters.