We use WRO300H units connected to our 5008S machines. We've used the 300 range for years and find them very robust, only have a couple of chem versions left to be replaced with H units. Only downside is no error memory and you really need a PC to set up all the functions. We don't find it too much of a hassle not having an interconnect cable to auto start/stop. We soften as standard on all RO's with a little 5L unit.
We've been using the Aqua Uno (cold disinfection only) for about 13 years now and find them pretty good. We have around 65 in the community. They come with a 5008S machines as part of a price per therapy package.
We have them remotely connected to the 5008S.
We visit them every 6 months to do a chemical disinfection with Puristeril. We also sample them just before doing this disinfection to try and catch them at the worst case scenario.
Only problems we have is the odd float switch failure (why can't Fresenius fit a leakage detector inside the case like the dialysis machine?) and pump heads losing output over time. Sometimes a dwell in citric overnight sorts out the membrane if it's that and not the pump head.
We only have about 3 of our home patients using a softener as we are blessed with lovely soft water in the north west of about 40-60ppm.
Our average conductivity of raw water is only 85-100uS. Our worst patient has probably 300uS.