I have a need to monitor my SpO2 for health reasons, so I use a continuous monitor most of the day every day.Pro's:- accurate. It reads exactly the same as the expensive big machines in the pulmonary rehab, but continues to read properly further into heavy cardio exercise before getting some interrupted readings from extreme movement. Surprised it outperformed the pulmonary rehab units... but it did.- small and light. I have others and this one is the smallest and lightest continuous monitor I own- easy to connect to your phone and get data. It just works... nothing special to do or buttons to push, couldn't be easier. The app found the monitor and asked me for the last four digits of the s/n on the back of the monitor the first time I connected to it. after that, I just open the app on my phone and it just connects and works.- continuous data. The fact it logs your readings so often (not like an apple watch that takes it once in a while and only when you are perfectly still) is very helpful to see exactly what makes your O2 saturation drop and for exactly how long, in real time and also historically with the app data. My doc thinks it's great I have this data for him.- Auto turn on / off - this prevents you from putting it on and going to sleep and not realizing you forgot to turn it on, or maybe accidentally turning it off. Also, there is no on/off button to malfunction over time. I was skeptical of this at first, but it makes it foolproof and works flawlessly.- good support. I asked the company technical questions about the data logging features and the app via email and they were quick to respond and answered thoroughly.- comfortable - this one being fairly small helps it be less noticeable to the wearer during everyday life and while sleeping.Cons:- the battery seems to last all day or all night and then some, but if you are one who needs to wear it 24/7, it requires more charging sessions per day than the long battery life versions. The vast majority of people buying these will never need to wear one of these 24/7, so this is irrelevant for most... and the small size is a great tradeoff for battery life for people who just use for exercise and/or sleep monitoring.- The cable for the finger sensor comes out right at your wrist and if you wear really low on your wrist will sometimes hit your hand if you bend it all the way back. Probably not great on that connector over time either. It's not really been an issue, but I think could be one day with heavy use.- The price is a bit high. Of course, it is a continuous monitor and has a great app and logs data, and given all that the price is reasonable given its a premium product and just works, but if you don't need all the premium features, the premium price is... well... premium. It did have a $35 coupon when I purchased it making the price $144.99 which is much more palatable than the original price of $179.99.