I'm currently shooting on a Panasonic GH4 and using the Panasonic 100-300mm and hear that the Canon lenses have better image stabilization. So what lenses (Canon/Sigma/Tamron etc) out there reach around 300mm (so no-go to the 70-200mm unfortunately) and have fantastic image stabilization? Ideally I don't want some huge and insanely expensive lens like the Canon 200-400 F4L either.