Heart Rate Monitors

Anyone use one? Any recommendations on which ones are the best and easiest to use?

I recommend something like the basic Polar FT1 HRM. If you go to the gym, most machines can read your chest strap, so you don't even need the wrist display. For the higher end monitors, I never saw real value in the features. All you need is basic monitoring to confirm you are in the zone, or when you've recovered enough to start another interval, etc.

I find that the calorie count on my Polar watch is not that accurate, but the heart rate seems to be. I use it to make sure I'm in the appropriate zone and to determine when I need to slow down a bit as Theo mentioned. Whatever you get, I'd definitely recommend getting one with a chest strap as they are more accurate than the ones that get your heart rate just through the wrist.

I have used them for many years. I just use them to keep in my target exercise zone, for which they are very effective.

I have posted this review of my HRM before, so I just copied/pasted it from a different thread:
Polar FT60F Black Fitness Heart Rate Monitor
I have had this since Christmas 2011 (gift from my bf that I requested) and have used it for all of my workouts since then! When you first set it up, you do a little conditioning test (have it on while laying down and staying relaxed for 3-5 minutes so it can test your resting heart rate/condition and estimate your VO2max) and then enter your stats - height, weight, age - so that it can calculate your calories burned. It keeps a fitness log of my workouts and tells me how many minutes I spent in each heart rate zone. At the end of my workout, it gives me a breakdown of my calories burned, heart rate zones, my max. heart rate, and my average heart rate.
You can set up weekly training goals (based on time, heart rate, calories, etc.) and it will give you feedback on your workout habits (I haven't used that feature yet) and you can choose to "lock in" a certain heart rate zone (1,2,3) for your workout and it has a little alarm that will go off if you go out of your target heart rate zone (either above it or below).
It has a chest strap (which is super comfortable and I hardly even notice it once it's on) and a wrist watch, so I think it keeps a very accurate heartrate - and the built in HRM on machines at most gyms will pick up the signal from the chest strap so you don't have to look at your watch while you're on the bike/treadmill/elliptical - added bonus..
It also has a HeartTouch function - when you bring the watch close to the chest strap it will beep once and show you the time briefly so you can easily see the time without going through menus.

Thank you all so much for your help. I really appreciate it!

Polar and suunto appear to be the most popular

Garmin Forerunner 410 - excellent watch with GPS and you can sign up with Garmin connect and have all your work outs uploaded and tracked.
It's only my opinion but I did a lot of research and I came to the conclusion that this was the best bang for your buck! I picked mine up at Costco for $170.00

I would strongly recommend a Polar Heart Rate Monitor and Watch, the monitor can fit into a bra or strapped on with the strap supplied. They are easy to use and are compatible with almost all CV machines at a gym. They are also able to tell you how many calories you are burning whilst exercising. Some of the monitors can also tell you how far you have run, and your average speed

I second the Garmin, if you're a runner. The heartrate strap works if you're keeping track of that for any exercise (not just running)and posts both to your watch in real-time and the Garmin dashboard when you sync, or you can run without it to track distance, speed, elevation, etc.

If you're not a runner, it's pretty expensive as a standalone HRM, in my opinion.

I recommend the Garmin 310 XT. They have a newer model out, 910xt but I can't recommend as it's too new and the price is fairly high.

I am currently experimenting with the Zephyr Bluetooth HR Strap mated to my Droid phone. This is all tied into Endomondo. I am pretty impressed so far with the Zephyr strap.

For sites that have a good amount of HR info try these.
http://en.wikipedia.org/wiki/Heart_rate
http://www.dcrainmaker.com/ for reviews