How often, or when, do you get the following items?

[Otaking]

Blood chalice - almost never unless on a hero with lots of early HP regen from items like HotBL or Shamans that spams skills quite often (for farming/harassing) . I find the following items much better.

Grave locket - on most int heroes or str heroes lacking mana

Mana battery - probably every game

Power supply - almost every game, especially when enemy got heroes with spammable spells

Ring of teacher - mainly on ranged heroes in side lanes that need some early game damage that also benefits from the mana regen. the armor is a bonus

Opinions? Tips from pro's?

[[VGG]Fairlight_Ex]

Strength heroes with small mana pools. It gives you +3 int for a slightly larger pool, and +3 strength for that extra little bit of damage/hp. Most str heroes can laugh off the hp cost after a few minutes into the game.

[[PiDs]Hunty]

Blood Chalise - All beefy heroes that need mana (Pebbles etc)
Grave locket - Almost every squishy/support early on
Mana Battery - Only VS armadon
Power Supply - Same as Mana Battery
Ring of the Teacher - Nearly every hard-support, squishies and armadon

[[Mana]Farosarg]

Blood Chalice - Not that often these days but all the beefy heroes or heroes that can easily get the health back without trouble can build it.

Grave Locket - Whenever I need early stats or just stats and can't get anything bigger on supports. It's solid pick on most of the heroes.

Mana Battery - All the time unless I'm playing versus a solo-lane who doesn't spam spells.

Power Supply - Almost all the time. I might get rid of Mana Battery if I'm having a good farm and am getting bigger items fast. It's really solid item regardless and worth building 90% of the time. It is so often that this item will make the difference between you dying and picking off a double-tap.

Ring of the Teacher - The armor is really solid and there are so many ways to take advantage on the item. In optimal situations both sidelanes should have one of these in your team. Put it on when you are diving to make sure creeps last longer against the tower. Put it on when you are taking the tower or want to pressure it. Build it when you know that physical damage is an issue. Build it when you know that you don't need any burst-mana and are getting solid passive mana-regen.

[Mankrik]

Armadon and drunken master are barely functional without blood chalice. Lego is nearly the same. There are plenty of heroes on whom blood chalice is not just a common or effective pickup, but more or less required in order to contribute. Can't stand seeing armadons and gladiators run around with zero mana and full health.

[What_a_Day]

I get a chalice on almost every mana dependant mid hero especially if he got good rune control. Such as