In your opinion, what is the absolute best cranking line for heavier deep cranks (3/4 oz +)?

I've always used Berkeley big game 10 or 12 lb

because of the price but lately I've had huge problems with fraying, memory etc. 

I use sunline sniper 12lb up to a 6xd and 16lb on a 10xd

If Big Game isn´t working properly for you then YoZuri Hybrid is your poison.

Fluorocarbon will help your line get down and stay down!

I use Yo-zuri hybrid on a lot of my set ups. Find myself going to it on more and more rigs too. I use it on my medium/deep crankin setup

10# CXX or 12# Tatsu are my favorites. 

Believe it or not but Sufix 832 in 40# test works great for deep cranks.  Casts a mile and the thin diameter gets them really deep.Have no any problems with fish coming due to the lack of stretch.

An added benefit is the ability to pull a plug loose from a snag 95% of the time due to the strength.

10 or 12 pound seaguar invisX

6 or 8lb diamater braid for me.  

30 lb braid with the drag backed off.

38 minutes ago, Yudo1 said:

30 lb braid with the drag backed off.

Braid is so buoyant it will work against a deep crank, and when you're trying hard for more depth you need every little bit you can get...

Without a doubt the best line for deep cranks is FC. Tatsu is the best FC on the market IMO, so I'd recommend 12# Tatsu. 

If you're one of those people who just despise FC, go with a copoly like YZH, as that will likely be a second best option. 

Ten or twelve pound Tatsu. Abraz X is good if you don't want to drop forty bucks on a spool of Tatsu.

I like 10-12 pound Big Game

For DD22's, 6XD's ect. 8 or 10 lb. Invisx.

7 hours ago, Evan K said:

Braid is so buoyant it will work against a deep crank, and when you're trying hard for more depth you need every little bit you can get...

Don't forget that line diameter is also a factor.  30lb has line diameter of 8lb mono.  I have no problem getting baits deep and I prefer the sensitivity I get from the non-stretch.  I can deal with vegetation better too.  Just my preference.

2 hours ago, Yudo1 said:

Don't forget that line diameter is also a factor.  30lb has line diameter of 8lb mono.  I have no problem getting baits deep and I prefer the sensitivity I get from the non-stretch.  I can deal with vegetation better too.  Just my preference.

Diameter is a consideration too, that's right.

11 hours ago, Evan K said:

Braid is so buoyant it will work against a deep crank, and when you're trying hard for more depth you need every little bit you can get...

not true at all.  The diameter of the line is more important to getting depth than the flotation of the line.  

3 hours ago, Yudo1 said:

Don't forget that line diameter is also a factor.  30lb has line diameter of 8lb mono.  I have no problem getting baits deep and I prefer the sensitivity I get from the non-stretch.  I can deal with vegetation better too.  Just my preference.

One trip to a lecture/demo with a viewing tank, where the speaker is using braid, and you'll change your mind about braid, and how the bow in the line created as the bait dives affects your perception of bites.  The bow is considerable, even with small diameters.  This was hammered home while watching a local "club pro" talking about the sensitivity of braid.  His plug was getting HAMMERED by 2'+ steelhead, and he never felt it.  A few sat back, snickered, and braid was never a consideration for deep cranking again.  If you have to use it, I recommend making a very long cast, well past your target, with water logged braid. Not saying it's wrong, or won't work, but there's some things to consider, based on my observations.