Anyone get any rustproofing / undercoating done?

I picked up a 2006 mazda3 2.3l which is in decent shape, only 95,000 miles about 150,000 km's and the shape is pretty good, I've seen other mazdas with worse rust especially along the wheel wells. Also here in Canada where I live we get tons of snow and cold temps with salted roads which ofc can't be good.

I spoke to some people and they told me to get it rust coated asap from underneath especially. Anyone running those coatings? If so is there one that's better than the other? I've heard of some names like Krown etc or just get whatever the local shop has done?

Thanks!