In a 1v1 situation it can be very strong, since it buffs every instance of damage (so yes, all the ticks + burning light).
But it can be hard to apply to a single target reliably for a magplar because of the nature of sweeps.
I do not have experience with it on a magplar personally, though, so can't offer you advice on how good it is there. It is, however, quite strong on other classes.