You can use it around town. Its not really needed, but its fine to leave it on. It is possible to bend the sway bar if you make a really sharp turn, as well as when backing up with it. The tech that installed and set up ours told me the same thing - just use it on the highway. I don't make a special stop just to take it on or off. If at a gas station or other stop, I might take it off if were are close to our destination. Otherwise I just wait until we stop to check-in at the campground and take it off.
2005 F-150 FX4
2013 Rockwood Roo 23 IKSS