The Wave Rebellion Pro 3 is Mizuno's marathon racer, built around a plate that runs out into the forefoot and the cut-away heel Mizuno calls Smooth Speed Assist. It is aimed at the front of the field — Mizuno's own description names a sub-two-and-a-half-hour marathon — and it is unusually light at 225 g for how much shoe is there.
It suits you on race day over the half and the marathon, and in the sharp sessions you use to rehearse them. The 4 mm drop and the truncated heel push you onto the forefoot, which is the whole point of it.
It is not a trainer. The heel is barely there, the ride needs speed to make sense of it, and easy miles will wear out an expensive shoe for no benefit.