What is your institution's practice/guidelines for considering a reduced-intensity (RIC) over a myeloablative (MAC) conditioning regimen?

We don't have an institutional guideline per se. Typically, RIC is used in older patients (e.g. above 60ish), second transplants, people with co-morbidities that preclude high dose therapy, and diseases that are particularly sensitive to immunologic control, or some nonmalignant diseases such as aplastic anemia. As a rule, myeloablative conditioning results in more non-relapse morbidity and mortality but fewer relapses. The opposite is true for reduced intensity regimens.