I will tell you that for 24/7 HR monitoring, the Fitbit seems much better than my 235. It does not sample enough, proven by the fact that when you pull up the HR page, the reading is way off for at least 15 seconds, when it really starts pulling numbers. It should be noted that this page will time out and jump back to the clock page in about 20 seconds. It is a terrible flaw, and hopefully this will be fixed with updates.