So I'm starting to give into getting a zoom lens for my E-M1 after months of telling myself I don't need one. Video is what's really pushing me, and I'd really like to have a weathersealed lens as well. This seems to be my only option in my budget. I don't want the EZ lenses as I like to have full control over my zooming, and superzooms are not my forte. This really leaves me with just this lens, or the 12-100 (which is super far out of my budget). Is this lens as good as I've heard? Or am I wasting my money?