Chubby, I haven't had any difficulty resolving 4 mana instants. Often times the situation is that I've traded most of my hand very early and then resolving a Gifts just doesn't do enough where resolving a FoF easily gets me back into the game and ahead of my opponent. And look at FoF vs. Painful Truths. One extra mana gets you a blue instant that doesn't cost you life and puts two cards in the graveyard. Not to mention 3U is probably easier than UBG. Instant vs. Sorcery is also a huge thing right now.
I don't think I've ever compared FoF to Painful Truths: I was replying to Khahan who compared Painful Truths to Skeletal Scrying. I think Painful Truths belongs in different shells from the one we are discussing currently, but that is a topic for a different thread.
