I'm looking to get a new heart rate monitor and my main concern is getting one that is able to track time in zone. My current one can do this but is limited to tracking 3 zones but I would like to get one that can track 5 zones. I would also like to be able to set these zones to whatever I like. I've done some online shopping and really haven't found anything that does this. It seems like all of the 5 zone HRM do not allow you to modify the zones. Can anyone recommend one based on these specifications? Thanks.