Not as fun as, and maybe even shorter than, Jumanji

Like I said back in 2013:

... following Sir Hammerlock into the untamed wilds to track and kill fantastic beasts, should be a blast. But this only happens in optional quests, and only a couple of times. [...] Dr. Nakayama [is] a truly (and self-admittedly) pathetic villain who, at the end, is actually terrified to fight you.

With its exceptionally-brief critical path, underwhelming final boss, sprawling and poorly-designed maps, and outright annoying enemies (the persistently-respawning giant spores!, the miniscule-weakpoint scaylions!, the face-armored savages, and their auto-healing witch doctors!), Sir Hammerlock's Big Game Hunt is undoubtedly the weakest of Borderlands 2's story DLCs.

Mr. Torgue's campaign wasn't exceptionally creative, but it at least met the bar of the main game's "average" content. Hammerlock's campaign doesn't.

It's just not very good.

Better than: maybe Red Faction: Guerrilla - Demons of the Badlands
Not as good as: Borderlands 2: Mr. Torgue's Campaign of Carnage, or even Enter the Dominatrix, which was like the worst Saints Row DLC.
But there's a light at the end of this tunnel: and it's a critical hit!

Progress: Bunch of sidequests left to do.