We have a Pur 35 that we sent back to the factory for service about 5 years ago.It works great.A couple of points.Go buy the book.How to Survive with a Power Survivor Watermaker by Gary E. Albers aboard S/V Ishi.
We ran into him in the Sea of Cortez where her put on seminars on the Pur 35 and 80''s
he demonstrated how to reseal them and all the other how too''s..
To install it needs to be out where it can be looked and serviced.The Prefilter MUST
BE where it can be looled at each time you use it.The overboard waste discharge is about 15 to one so you need a good place to discharge.Do not plumb the good water into your system.Fill a container test it with a
TDS meter.Drink some for the final test before pouring into your tank.
All w2ater makers are happiest when they are
used daily.I run ours about 2-3hours every
other day whether I need the water or not when we are underway cruising! Good laundry water also things like
winches and blocks like non-salty baths too!!
If I had to do it today I would get a watermaker with a Clark
Pump!