Yes, it will give you a caloric number to shoot for depending on your activity level regardless of a monitor. The heart rate monitor makes it really precise because you can take your RMR x PAL factor results, subtract your weight loss calories, and then add in exactly how many calories you are burning during your workouts.
With my slow metabolism I have discovered that I need to always subtract 300-500 calories from my RMR x PAL results and then add back in my calories burned during exercise in order to maintain my weight. However, I've been tracking my calories like this for so long that I rarely wear my monitor anymore; I just use the RMR x PAL number. I use 1.3 for my PAL factor since my workout is the most strenuous part of my day. The rest of the day is rather sedentary at a desk or doing normal housework.
So my equation looks like this (I weigh about 130): RMR 1275 x PAL 1.3= 1657.5 calories/day for maintenance.
If I wanted to lose a few pounds, I would subtract 300-500 from 1657, and then add back in my workout calories from the reading on my monitor (to be very precise).