My experience about the soft lenses is that they are quite safe, but under certain conditions.You should not use them for over 6 hours continuously.Ofcoarse needless to say, the hygiene of handling them and washing in special solution is a must. Also never have them on when you sleep or even have a small nap. With eyelids shut, you are starving your eyes of oxygen/air.
Most important they are not suitable if you have DRY eyes. This is dangerous, as you will tend to scar your eye surface, causing discomfort, redness in the eye and even more serious problems.Hence if you ever suffer from eye dryness, or feel like rubbing your eyes, stop using the lenses immediately, and see your eye doc.Never sip hot liquids like tea, coffee, because the heat is too near the eyes, and the lenses might get warped or crumpled, losing the shape permanently.
Keeping all the above in mind, its quite safe sailing through your day without problems.
Finally dont forget to remove your lenses at night when you sleep. Always keep your thumb and forefinger nails closely clipped and with smooth edges. All the Best to all soft lens users.