Help please....

You're looking at two different devices.

1) A fitbit or similar pedometer to track steps.
2) A Polar or Garmin HRM (Heart Rate Monitor) to estimate calories.

If you don't care about accuracy as much, the Fitbit will basically estimate your calories as well, although a dedicated HRM will do a much better job.

The most accurate HRMs come with a chest strap. Price depends on how "fancy" you want the HRM to be. I bought a very basic New Balance N4 HRM from REI for about $55, and use it everytime I exercise. I also use it in conjunction with my FitBit One because it seems more accurate at calculating exercise calories, and the FitBit isn't that great at determining calories burnt during non-step related exercises.

In my opinion, the Fitbit is more accurate than an HRM. HRMs are not good at estimating calories for most people, especially if you're not a very fit person to begin with. Heart rate isn't a very good proxy for calories burned, especially if you don't know your VO2max and can program it into your device.

My Fitbit has been extremely good for me. I've followed its calorie burn recommendations for about 5 months and have lost exactly the weight I'd expect to have lost based on its predictions.

What fitbits / HRM's you guys got? I'm not looking for anything particularly fancy just something that can see how lazy I am during the day lol and to calculate how many calories I'm burning running, doing insanity and classes etc.

I use a Fitbit One. This is what I've been able to do with it over the past several months:

Which fitbit? there is several and I don't really get the difference in them... That graph, what have you aimed for with your fitbit to get those results. I'm currently trying to lose weight for my wedding next year but struggling =S

Would fitbit track calories from insanity?

All the Fitbits basically do the same thing. The Zip is the cheapest; it has a replaceable battery that lasts several months. The One has a rechargeable battery that lasts about 5 or 6 days between charges; it also tracks floors climbed, which is great. The Flex is wrist-mounted. IMO the Flex is problematic and I recommend not getting it, since the wrist is a poor place to measure body movement from.

I recommend the One. It's a great device.

Anyway, I have synced MFP and Fitbit. I log my food in MFP. Fitbit adds a calorie adjustment to MFP. I basically aim to end each day having eaten about 500 calories less than the Fitbit estimates I've burned. Actually I lowered that recently to about 375 I think because I only have a few pounds left to lose.

I think the Fitbit would do pretty good tracking calories burned during Insanity. It doesn't do very well at strength training because you're not moving much. I log weightlifting as an activity on the Fitbit website to add a few extra calories per session (like around 50 per hour). HRMs vastly overestimate lifting calories

That sounds great! I love how your working it with this! You eating clean and really well or just making sure calories are 500 under? Does it calculate calories burnt from classes or insanity as opposed to walking/running?

I think "clean" is a nonsense word.

I have macronutrient goals. I make sure to hit my protein, fat, carb, and fiber goals and I make sure to eat veggies to fill out micronutrient goals. My diary is open, feel free to look at it. I eat a lot of ice cream, fast food, etc. But I also eat home-cooked food too.

And yeah, the Fitbit is good at measuring calories during any activity that involves you moving your body while on your feet. It's not good for something like cycling or skating or swimming. But you can still log those calories on the Fitbit or MFP sites.