Amazing location. The street itself is relatively quiet, but tons of restaurants, etc. just a block or two away on either side. I particularly appreciated the small market just before reaching the Rue du Bretagne, as it allowed me to pick up fresh vegetables, cheese, fish, etc. less than five minutes away.
My only words of warning are that the apartment is quite small (just, it should be emphasized, as described in the listing), so I wouldn't recommend it if you are planning to spend lots of time indoors. If, however, you're planning to spend most of your time wandering around Paris, as I did, it couldn't be better.