I will say, (speaking as a playtester of sorts) that the times I typically get when playing good have constantly been twice the estimated time.
it also seems a bit off-balanced with there being so many relics and consumables that help you with reducing click count and not taking damage, (and I'll even count the radar as helping you go flagless, since it doesn't actually count as "using flags"), but pretty much only a single relic that helps you save time.