It heavily alters vanilla gameplay. Frankly, xcom becomes another game, more imbalanced (because AI can't use that, and hardly be able to). Obviously it's aimed for making player's life easier, deaths uncommon, and generally it's damn cheesy.
I wouldn't suggest adding this "feature" in first hand, if it's up to me. At least not in "advanced options" but for some total-conversion-mods only. Not to spoil vanilla.