Jenny, Any update on what you ended up doing? I installed a whole house softener for hard water issues, but I have odor issues (sulfur and chlorine mostly). I'm leaning toward adding a charcoal filter before the softener. We also have RO in the kitchen and wet bars. Also, you could always just have another hole drilled for the RO faucet without replacing the granite slab. If you have an undermounted sink, the new hole is all you need. What did you end up doing?

Be advised that there are NO whole-house filtration systems (at least none that are worth anything) that require no maintenance....unless what you mean is that they do it for you. Suggest you define your purpose. Taste can be easily handled by RO with nothing else. If you want soft water for laundry/batheing, that's a different issue. If you want specific filtration for other specific concerns that's a different issue.

My suburb purchases its water from Chicago. The water is not considered hard and homes on Chicago water typically do not have a water softener. Over the years, the smell and taste of chlorine has gotten much stronger - either I'm getting more sensitive to it or more is being added to the water. I was using an under-the-sink filter with 2 cartridges and the single cartridge units that are placed ahead of the shower head. When I touched up my main bathroom 3 years ago, I decided to scrap all the separate filters and install a whole house filter. I purchased this one from Discount Filter Store: http://www.discountfilterstore.com/two-housing-filter-system-pentek-bbfs-22.html and two cartridges - one for sediment and one a carbon filter. So far, I've been totally happy with it. I did not notice any pressure drop and no more chlorine taste or smell when taking a shower. The cartridges are cylinders, 20" long and 4.5" in diameter. Together, I paid around $90 for the pair, last time I replaced them. When replacing them, you have to wash out the housing with a chlorine bleach solution and then install the new filters. Because of the size of the housing, that's something best done in a basement laundry tub. Then there's new o-rings and food grade silicone lubricant for the o-rings. Definitely not as easy as replacing the under-the-sink versions, but once installed, every faucet, shower and tub are covered. Unfortunately, also every toilet and sill cock (I didn't have the house re-plumbed). However, since my water usage is low, I only change the filters every 2 years - have only done so once; time to do so again is coming up. Since I have a meter, it's easy to know how much water is used vs. the rating of the filter. I had a plumber install the system for me. He put in a full complement of ball valves such that I can bypass the filters and still have water in the house. I also purchased the special wrench that fits into the grooves of the housing making it easier to remove.

How about a follow up -- a way late follow up ... So the filter is supposed to be a whole home filter, because the city has super old pipes with a lot of sediment. However, the filter needs to be changes monthly, and my sister had no idea. She (unknowingly) let it go for years. It was so backed up that her house barely had water pressure. It should have been an easy fix when I went to help her, but the 100+ year old house had a faulty main shut off valve -- as well as the pre-filter valve being faulty. So she had to call a plumber to contact the city to shut off the water at the street/sidewalk. There was nothing I could have done from there, the city won't turn it off for a homeowner (unless they don't pay the bill, lol). She now gets 'subscribe and save' monthly filter deliveries from Amazon to remind her to change the filter. Luckily, the plumber was able to blow the back up sediment out of her pipes, and she didn't need any pipe replacement. Her water pressure is now back to the usual crummy-100-year-old-house water pressure, instead of the even worse pee dribble pressure that she had with the backed up filter and pipes. Thanks!