Lee Sin Build - Attack Damage, critical strike, or tank?

Hi there,

I'm a new lee sin player, (only have a few matches under my belt), but I am really enjoying him. There is something mildly satisfying about landing a sonic wave on an unsuspecting enemy, then flying through a wall to kick them in the face!

My problem lies with his item builds though. I have found many guides telling me to build damage items; black cleaver, duskblade... etc. But when I play with him in the practice tool, I almost feel like critical strike and attack speed work better and deals more damage, but I could be wrong.

Also, is just going pure tank viable for lee sin? Does he do enough damage without needing all offensive items?

Thanks for any help!