Treadmill Accuracy Question. Help Me

So, I have a very expensive treadmill that cost about $1000.00. You can put your weight/height/etc programed into it and customizes workouts. I normally do a power walk that is borderline jogging, for 30 minutes and my treadmill says I lose about 360 calories during that half hour. I figured that a more expensive treadmill would give you more accurate results regarding calorie loss, but I could be wrong.

Then when I use MyFitnessPal's fast pace walking to track my exercise for the day, it says I only lost about 140 calories.

So I'm kind of confused as to which one to go by. I eat my calories back from working out because I already stay in a very limited daily calorie intake and everyone encourages me to not eat less then 1200 calories a day. I don't want to eat to much, by going by the treadmill or eat to little by going by MFP. I don't know which one is more accurate!

I'm 20yrs
Female
180pounds 5'8
and I eat 1300 calories a day