Because my sofa had a big camel back, and I didn't want to tuck in my cushion, I bought a separate cushion cover. The sofa slipcover was easy to put on and has stayed in place except for the back bottom, which I stapled underneath as the sofa isn't against the wall and out of sight. The overall fit was ok but not perfect due to the shape of my couch and larger arms. The cushion slipcover was a tad darker even though I ordered the same color grey. 

 Overall, I am happy with it, but can't wait until I can get my couch recovered this next year and have the back pillows match the two chairs opposite them that I had recovered a few months ago.