which one should i buy for TT? need your help on this one

Not akali, with stealth revealing items you can make her W a non-factor, the same could be said for shaco - but his stealth is typically engage or disengage not "here i am, fight me". Shaco has a much larger map presence all around

I've seen stine good akalis. But only when they dont rely on shroud to escape. They utilize it to slow,or lower defense, but are smart enough not to try and hide in it if the enemy has vision item.