Now i've been wearing contacts for about 3 or 4 yrs now and these were recommended by my eye doctor. They can be worn for 30 days and 30 nights straight but I wouldn't recommend that as the protein on your eyes can build up. These are the only contacts I've ever tried and I like them very much. They don't cause discomfort or irritation either. My opinion overall is that these are a totally good product and they're fairly reasonablly priced. To buy a whole yrs supply is actually cheaper than buying a brand new pair of glasses every year.