Yes, it is plenty safe, provided you aren't drifting, or doing stupid crap. A YJ is much more stable than a CJ or TJ due to the spring placement & the use of leaf springs. You will notice a bit more body roll, but again, it isn't a street racer, and should be driven as such, especially if it is lifted.
It took a bit of convincing by the YJ guys here to get me to pull mine off, also, but it's well worth it, off-road, and virtually un-noticable on road.
If you plan on your YJ being your daily driver, and trail rig, then pull them off, and use the front anti-sway bars on road if you feel a little uncomfortable with the body roll, and then disconnect the front when on the trail. If it's strictly a trail rig, cut all of it off.