Go with a Fleck or Clack valve and 10% cross-linking on the resin. Buy it on the internet.

Check www.ewswater.com

@rachel custom sinks:

Why? He's looking for a water softener.

Todd, just get a properly sized and configured water softener. You don't need to spend $2k. There's no special sauce - no softener is going to get the water "more soft" than less than 1 gpg.

It's a commodity process - the only way it can go wrong is if you get sucked into stupid stuff, because you don't believe a $700 softener is good enough.

If you aren't a diy kinda guy - talk to a local water treatment company. You just want a water softener... don't get sucked into the nonsense.

Many years ago I found ohiopurewater to be very helpful. https://www.ohiopurewater.com/

There's a lot of good information on the site. You can call to get help with sizing and features of the valves. I've forgotten much, but my recollection is that softeners don't help with TDS but do remove a small amount of iron. Don't be surprised if you're steered toward a sink RO system for the TDS for drinking water. You might want to ask if you can get fresh media for the resin tank and reuse it - one less thing in a landfill.

@Jake The Wonderdog I was simply recommending what I used for 13 years without ever having to add anything, check anything, etc. It just runs and purges itself. I do not sell the whole house units, just passing on my great experience.