Rushing Aghanim on Rubick - Justifiable?

I think this would be balanced, after all, Invoker gets whichever of his 10 spells he wants every 2 seconds for no Mana with an Aghanim's Scepter. Rubick has much less control over which Ability he steals and there isn't always a good selection to choose from. Removing the Cooldown and Mana Cost completely would be fair imo.

Voted never. It's a good item but since Rubick is never seen at mid anymore, he's pretty much relegated to 4/5 roles, where your first "big" item will be a 25-30 minute Blink Dagger or Force Staff (and I've had a lot of games where I had to get the Mekansm).

I make Aghs as my second pickup, but it's very rare that I get rich enough or the game goes long enough that it gets finished.

True, but invoker's spells are all pretty mediocre. The ability to steal 2-3 ults in a team fight for 0 Mana would be broken. While invoker can tornado, meteorand blast... Rubick would be able to ravage, sonic wave, and black hole. It's comparing apples to oranges since Rubick can use a huge ultimate, then replace it immediately with another good spell. Meanwhile tidehunter has... gush and anchor smash.

Im not a good rubick player myself, but i enjoy playing the hero. How often did it happen to me, that i wanted steal that big teamfight ultimate (like Ravage or Reverse Polarity) but when it actually happend, i was caught in it and my team died before i could use it myself. Therefor the range increase sounds awesome. The 5 second cd sounds even better tbh. If you are looking for huge spells to steal, you naturally try to keep your Spell Steal off cooldown and therefor you have to ignore a lot of good spells. So overall i think it would provide some really good utility.

On the other hand however, a position 4/5 rubick will never be able to afford this item...especially if he also want to go for that Blink Dagger, which is exactly why i would vote for the second stated answer.
But hey, who knows....maybe Mid Rubick - like Pepo said - will be viable again ^.^

An enemy Team being bad enough to let a Rubick steal Ravage + Sonic Wave + Black Hole in one Teamfight does not make 0 Mana + 0 Cooldown Spell Steal OP. You'd think they'd at least catch the Rubick with the Ravage or the Black Hole, or have some other way of dealing with him.

What about Rubick stealing Ravage, Stealing something else and using Ravage while the new Steal is en route, re-steal Ravage (since Tide would be stunned with the Ravage), rinse and repeat until his mana run out?

Or maybe Doom. Steal Doom (hopefully it's your Carry who took the Doom), cast Doom on Doom, Steal something else, re-steal Doom (0 cd), Doom someone else, Steal something else, re-Steal Doom (since Doom's Doomed and can't cast anything else), Doom someone else until all 5 enemies are Doomed?

Also that's alot of Doom in a single paragraph.

1. Mana problems.
2. I don't think the cooldown of a spell you use gets resetted if you get another spell.
3. Doom Doom Doom Doom.

1. I suppose Dooming all 5 is implausible, but maybe 3-4? Assuming Rubick only cast Spellsteal and Doom.
2. http://www.youtube.com/watch?v=0e8euzMnGww
3. https://www.youtube.com/watch?v=fqcn_TPu4qQ

True, it would also have to be reworked so that spells retained their Cooldowns if you restole them, since I've never gotten a Refresher Orb, I was unaware of this. ._.

Worked well for me but it depends on if you can get the necessary farm, I took the speed gaming route and played greedy Hand of Midas on a 4 slot rubick (our CM did the same) I ended up with mana boots, aghs, and a force staff, as well as the levels to compensate for the time spent in a safe lane trilane. Ended up stealing Death Pulse to save a TA from Reaper's Scythe, and stole that too to finish Necrophos off, and took on a terrorblade that same game by stealing Metamorphosis (+80 dmg rubick in demon form triple kill=priceless) and blasting away before he could Sunder. Well it helped I had an Invoker cast Alacrity on me, but hilarity ensued l. Aghs is awesome, just don't zero in on it and expect it as a viable option every game, sometimes you just won't have the gold and will be pick up Mek , force staff, blink etc