>>3891754>underexposed C41 doesn't look very good so it makes total sense.Not the anon you're replying to but are you saying this from experience or from reading other people say this? You're right, at a point underexposed c41 doesn't look good. A stop difference though? You won't even be able to tell the difference (except mayyyybe with Ektar).
If you don't believe me, give it a try on your next roll. Next time you're shooting a roll at box speed take a few identical frames one exposed correctly and another underexposed by a stop. Hell, do another frame underexposed two stops. Get the roll developed normally. I bet you'll be surprised at how difficult it is to tell which on is which when you get the negs back.
Shooting a roll of 400iso c41 at 800 and paying a lab to push it is a waste of money. Pic related: Portra 160 rated at 400 and developed normally.