I just got a Nitrum 30. I am a 29" draw. The cam I got is the 28-30" and I believe its the 2nd one. Sorry forgot which they called it.
Now for sure get your draw check. What I do is have someone stand sideways to a wall, then stretch their bow arm out, the one holding the bow, straight to the wall with your fist flat against it. Now have a slight bend in your arm cause nobody shoots straight armed and you want the bend like a shock absorber. SO then have someone measure from your fist against the wall, take the tape measure from the wall to the corner of your mouth. That's how I always come up with ones draw length.
I have a loop as well on mine and have it tied as small as I can so there is smallest gap from the string to the caliper head. Having a draw length too long is bad, its better to be short than long any day. You will have more control.
What I would do if you want to be certain, is go to a dealer with your release. Draw a 29" and a 30" both back. Honestly I don't know if they come in a half inch increment. But I would go draw those 2 draw lengths back and go from there.