For a low-cost Freediving watch, this is the perfect purchase. If you are a spearfisherman or a freediver who doesn't want to dive down and keep worrying about how much down time they have left by always looking at their watch, this is the fantastic choice. Different parameters can be utilized. As a freediver myself, the Salvimar watch should have been on my wrist years ago. What does it do....1. It has a setting that tells you when you have reached the depth you have programmed in and warns you when you are deeper than you might have originally wished you wanted to go. 2. You can set it so it tells you that you maximum down time has been reached and alerts you that it is time to surface. 3. The diving function has the Water temperature where you was and after you surface, it counts how long your head has been above water before you go back down (Recovery Time). How safe you are is up to you. You know how long you can stay down and how comfortable you are at what depth you choose. The depth sensor is spot on with the actual depth. The watch has all of these different features programmed in to keep you alerted. The land functions (Time, Stopwatch, Daylight Savings Time, and other times in other time zones) are also big attributes to this watch. Well done. I hope that the previous reviews about durability with the watch not holding up is just simply how it is taken care of and how it holds up for years to come. It did a little figuring out to get everything set, but once I figured that out, it's pretty awesome. The biggest thing I did notice is it clearly says, DO NOT PUSH BUTTONS UNDERWATER. The way this watch is designed, the buttons should never have to be pushed underwater. Simply push the start button before you start to descend. Everything else initiates automatically as you swim down. I hope you enjoy your watch and I hope this review helps makes a good buying decision for you. So far, my watch has the 5 Star rating.