pro : this have be a great device ! I have use it every week for a little over 2 year . this device be a great training tool . it be very convenient to head out for a run -lrb- work with a bike also -rrb- and have instant feed back on current heart rate , average heart rate , pace -lrb- cadence on a bike if you have the adapter -rrb- , average pace -lrb- cadence -rrb- , distance and time . I can run when I travel , and I do not need to pre-select my route ! if I want to run 10 mile , I head out and run until it tell I I have travel 5 mile and then follow the same route back . there be even a mapping feature that you can follow you route back , if you feel like you be lose . it come with software that you can install on you pc and see how you have improve , both in heart rate , pace and distance . I use it to know when it be time to replace my shoe . I buy new shoe every 300 mile , and with the software I know exactly when I have run 300 mile . if this device be to quit work tomorrow I would head right out the door and buy another . con -lrb- only one I can come up with -rrb- the heart rate strap , be the only thing I have ever have issue with . I have read many forum and several review , and it seem many folk have have the same issue . if you start get erroneous reading with you heart rate , first replace the battery , and or check the copper connection inside the battery compartment . simply bend they out a little to hug the battery tighter will correct the issue . if this do not work , you can buy a new Heart Rate strap . I have use the Garmin Premium Heart Rate Monitor -lrb- Soft Strap -rrb- , which be more comfortable to wear , but only work for about 2 month . I try all my battery trick to no avail . I purchase the Garmin Heart Rate Monitor , same as the origanl monitor that come with the device , and it be work just like the original . I expect I will be replace it , in a year or so . that seem to be the lifespan of the strap , base on personal experience and other review . bottom-line , for the price and what this device offer , I would recommend this device to anyone . -lrb- I would have give 5 star if , it be not for the hr strap issue -rrb-