It's very hard to control, but it's kinda fun anyways. The slowmo mechanic is kinda weird to use too, sometimes after you slowmo doesn't let you do it again instantly so reaiming is very difficult; maybe it's the intended way.
The slowmo has a 0.2 sec cool down to force the player not to just perpetually remain in slowmo. I think if you get used to how long the cooldown lasts, re-aiming is fairly doable. I will admit though that I ran out of time to tweak these values to make it feel better.