How much rest should I take during SAQ training?

It depends on what you are looking to achieve from your individual workout and how the SAQ workout fits into your overall training plan. Whenever you train with limited rest you are focusing more on conditioning and less on speed, agility, and quickness development. SAQ training is very tempo specific - so if you intend to significantly impact those attributes, you must perform with the utmost intensity. In order to deliver the intensity necessary to truly develop SAQ, you must have adequate rest between those efforts. The wise SAQ program begins the off-season with high intensity exercise and long rests. As the off-season progresses, high intensity is still required, but modified to  meet the best of the athlete's ability as rest periods progressively decrease.