I would recommend one of these at a minimum.
http://a.co/eD3ixCiI had the plumber take the incoming water to the garage and put in a loop, which basically is one line coming from the wall which is from water supply, and then the second line from the wall goes to the house.
Like this:
Definitely put a shutoff on the incoming side so you can turn off water if you ever have to change the housing out.
So all the water in the house is filtered. This helps everything and prevents crud in the lines, sediment, scale, calcium, and chlorine. Water heaters, faucets, refrigerator all benefit from less crud in the lines over time.
I got mine at Home Depot 12 years ago. Filters are $12 for two. Change every 2-3 months.
Is it as good as a $1,700 system? No, does it make a difference, absolutely. Water taste better, checked water heater that had been installed for 5 years and no crud in it at all.
Also, I like that it is clear as I can do a visual check when my water company repairs a line and shoots sediment into my filter.