i LOVE rear projection. on the one hand it can be shockingly convincing - it took my years to realise this shot in “The Shining” was an elaborate sideways rear projection set-up.
but you can also take advantage of the technique to weirder, less “realistic” effect; the static bus shots in Kiyoshi Kurosawa’s “Cure” use it (unless i’m very mistaken and it’s a real set) to create a weird, swirling fog dimension that feels subtly wrong and unreal, perfectly fitting the feel of the film