So is the question whether going the big monty 40 is worth it? Or perhaps more is just more, and what would it compromise?
I don't think there's necessarily a right or wrong answer as both are prodigious in terms of added capacity. It's going to come down to how you use your vehicle.
As there's no cost difference between the two. And unless you're really really into rock crawling where clearance doesn't seem to be an issue. I think the discriminator potentially comes down to weight.
I don't know how much more weight the 40 gallon subtank is over the 24. But it is going to be incrementally heavier. The tanks are about 100lbs IIRC. Then there's gas weight at ~6 lbs / gallon. 24 gallons is 144 lbs. 40 gallons, 240 lbs. Between the tank and gas, the 40 gallon is going to put another ~350lbs on your rig, which is definitely something you will feel and will take a bite out of performance.
I said potentially earlier as you could of course not fill all the way. At which point it's just the incremental difference in the tank weight itself which I'd guess to be ~25lbs?
The wild card and might be hearsay...I'd read something about being able to feel fuel sloshing with a partially full 40 gallon tank?
I'm personally critical of weight as I want to keep as much payload for hauling.
As someone that has the 12.5 gallon baby tank. I'm content with my current 500+ mile range. 24 would put that to almost 700 mile range. 40 gallon, almost 1000 mile range.
Does anyone need 1000 mile range, where 700 mile range wouldn't be enough? Only you can answer that.