Monitors

Options
I have an Omron monitor from REI for walking & a Polar monitor for biking to record steps/calories/heart rate. What I want to know is what are other people using to monitor heart rate on physical outings? I was told that they aren't accurate if you are on high blood pressure medicine but I need to watch how hard my heart is working because I tend to really push myself during work outs.
So....what are you using for monitors. Likes and dislikes.? Jane in Montana