Yeah, Aspected Helios you have to stop moving but literally for 1-2 secs. Normal Helios you can cast while running, same with Benefic II, Exalted Detrament, trying to think of some others. I don't use it for Aspected Helios, usually just for those times when the whole party is under 50% HP. Lightspeed plus a few hits of Helios usually brings everyone right back up, and the 25% MP reduction is a huge help.