Mismatched Spare Tire? Cons?

I'll be getting a new set of tires likely within the next couple of months as the wetter season is upon us and my tread is running low, and with that, I am trying to stay within my budget. I've opted for 275/70/17s BFG KO2s for my first gen as I think it'll be a good middle ground between the more than 1/2" larger 285s and the 265s I currently have.

While I know the KO2s just about always run pricey, I am trying to cut a bit of a corner in the process of replacing my spare tire. Rather than paying another $400 for a tire that will most likely(and hopefully) not have to be removed from the bottom of my truck bed, I've been on the lookout on Craigslist and local tire shops for a tire spec that fits with the 275's that is on the cheaper end due to it being used/a single tire compared to 4.

Does anyone have any input on some cons behind this apart from the tire not matching the other 4. For me, when I think about it a spare will likely only have to be put on for a short period/distance until I can get a replacement, so why pay the $$$ when I can save it for other endeavors? To add, I am looking specifically for an AT tire in the case that the spare needs to be replaced when off-road. About 10% of my driving is offroad, and it's nothing special, typically just service roads that lead to BLM land for camping/hunting and whatnot, so I am not too concerned about NEEDING a matching tire to help get me out of somewhere. Thoughts please

 

No cons. Rock that bastard spare

 

I think you’ll be totally fine...so will your truck. The spiders gears that are inside your diff’s carrier will handle the slight tire diameter difference. If you’re REALLY concerned, you could also do a musical chairs with the tires and swap the flat tire to the front (if you get a rear flat). If you have a full locker or a tight limited slip in the rear diff, then i would also swap tires around so that the spare would be in the front. You’ll be ahead of the game (compared to many other drivers in the road) by just by having a spare tire that’s fully inflated. This is all coming from a guy who just this weekend removed a 10 year old BFG AT 265/75-16 from under one of my other trucks. The BFG has zero miles on it, but now it’s also beginning to get cracks in the rubber. Money wasted right there.

 

Did that on my 19 when I upsized the tires.

 

I did the same.
Check tirerack and discount tire for their closeouts that they only have a couple left of.

I found a Goodyear Adventurer with Kevlar for like $150 on TireRack.
Used it for 2 weeks when I got a screw in an unhappy place and was waiting on wheels and tires.
Now it’s happily back up in its place.