I have both - I bought Country Living on release and Eco Lifestyle a few days ago.
Country living is a must if you like animals, farming, gardening, the country side in general. For my gameplay these things are central, so this game pack is fantastic for me.
Eco Lifestyle has a lot of gameplay and cool BB and CAS stuff, yet, after 1 day I personally felt I had no more interest in playing with it. Two of its main features are the NAP voting and the Eco Footprint, which I keep disabled ( you can disable them in the game options). Note that if the option of disabling them hadn't been available I wouldn't have bought the game at all.
Another thing to keep in mind is that Eco Living might still be a bit glitchy. I had never had any problems with my game, even after buying Cottage Living but as soon as I got Eco Lifestyle, a lot of things have stopped working. I don't use mods or CC, and had all patches, so it was really disappointing.
