I like foils if I have them, but I don’t really go out of my way to chase them. I double sleeve my commander decks, so most curling isn’t an issue, but some cards out there are really bad. I’ve had them curl immediately upon opening a pack.
If I’m buying a card for a deck, I’ll probably go foil or special art, but it depends on the price. I play casually with friends, so it’s more to show off cool cards with them.