I started with Super Joints, then about a year later I got the 3 part Warrior Wellness set. Since then, I've added to my program from Sonnon's Body Flow, Freedom by Degree, and Intuaflow.
I'd start with the Intuaflow if you are new to DROM. It is a 4 level program that replaces the older Warrior Wellness material. It has some Body Flow stuff added, plus vibration drills.
I don't follow any particular program anymore, rather treating all of the drills from many the programs as tools in the toolbox. I go by feel or time available for the day. You will learn to create movements specific to your needs. I most often use the "beginner" level simpler movements, really slowing them down to feel any hitches in my movement. More complex or faster drills I tend to do prior to training.