For me, it depends upon the team. I almost always run Offensive Utility Tusk (Boots 4 Attacks w/ KO, RS.) It has a lot of power and bulk, and can apply a fair bit of pressure when positioned properly. There isn't a whole hell of a lot that wants to come in a Tusk if it's played well.So I finally bit the bullet today and got over my distaste of Great Tusk and I gotta say.... I'm kinda whelmed by it.
The way the usage rate and people talked about it, I was expecting something mindblowing once I slotted it on my team but so far he has been... just OK? I'm probably missing something, like a specific set but so far I find myself liking Iron Treads or Landorus over him.
The major thing about Tusk is the role compression it provides. Defensive tank? Check. Offensive pressure mon? Check. Spinner? Check. Item control? Check. Rocks? Checkerooni.
Treads can do this to a lesser degree. Steel/Ground is great for resisting Rocks, and having a raw immunity to TSpikes, but you trade raw bulk and power for speed. Steel/Ground also hits less than Fighting/Ground offensively, even considering overlapping coverage.
Lando-T... Does Lando things. Except worse this gen. No Defog or Knock for it really hurts how effective Lando can be, but it makes up for it with Intimidate and one extra immunity over Tusk. You're also naturally faster. Lando has more offensive options than Tusk, but less raw bulk and a harsher 4x weakness to Ice (which is seemingly rare these days.) Buuuut you COULD make use of a Mixed Lando if you really wanted to, or god forbid a Nasty Plot set. So you have options for surprise factor.