"Steven, why do you think the ISF mode is "blacker" - I see no evidence of that - panels have a "native" black level that does not change in different modes. The only time the Kuro panels get darker than their native black level is when you leave an all black screen on the display for some period of time, in that case, after a time-out (30 seconds or 15 seconds or something like that) Pioneer turns the panel off completely and the black is just as black as when the panel is turned off - but you never see that "total blackness" in any image. As for "more lumens" - you probably mean more foot-lamberts - it's just not necessary for viewing movies or TV in a dark room. In fact, making the picture brighter than Pure mode allows in a dark room will cause squinting and/or eye-strain because the screen will be too bright for comfortable viewing in a dark room. If you want more screen brightness for viewing with daylight in the room, ISF mode is completely unnecessary as the light coming into the room "de-calibrates" the TV anyway. There's no real benefit from using ISF-Day or Optimum or even Standard mode with daylight in the room because the daylight changes color constantly during the day and because the daylight make calibration impossible.
The ISF modes may "sound good" on paper, in real-world viewing, they don't really do anything very helpful, except give you modes that block out all the user menu settings so that other family members can mess with your calibrated settings."
Homer cosa ne pensi?