I know this is an older thread but if you're still looking, I recently bought this on Amazon and love it:
https://smile.amazon.com/gp/product/B004K25GMG
I have a ram power wagon that runs 60 psi on-road and I usually air down to around 35 offroad, though I would go lower if I were in sand. This is a little bigger than one of the mini cig lighter compressors so it's harder to stuff under a seat, but airing up only takes about 20 minutes total to get back to 60 psi. Those cheap little 12v compressors just take forever - they're good for an emergency tire fix if necessary but they're not built for consistent use on big tires.
FYI 35 psi is too high for daily driving
For offroading, 15 psi is the standard go-to pressure. I wouldn't go lower without beadlocks
There's 3 main routes to go for air
1) 12 volt air compressor
2) CO2
3) York 210
12 volt air compressor is by far the most popular due to the simplicity. You put it in your Amazon cart, you wait for it to ship to your door, you stash it in your jeep storage until you need it, and you just connect it to the battery terminal and air up. Of course there is different styles of air compressor set ups, but that's the idea.
12 volt is typically the slowest, but is the most practical route
CO2 is the quickest and almost no noise. Down side is you have to go to places that will fill it up, and that costs money. If you're out on the trail and run out, you're out, that's it. CO2 is perfect for some people, probably not the most preferred by most, though
The best, but potentially the more expensive option, is a York 210.
York 210 is an old style AC compressor that easily converts to an air compressor and runs on your serpentine belt.
If you're savy, you can get a York 210 from a junk yard for around $60. If you're somewhat capable of fabricating, you can make a mount for around $20. Tack on about $120 for odds and ends (longer serpentine belt, hoses, fittings, possibly a new pulley, etc)
If not, you can buy a York 210 New from Amazon and a bracket kit designed for your jeep
In short:
All 3 options are all options that serve their objective perfectly well, it comes down to which one fits your wants and needs the best
York 210 is the best route to go, point blank
CO2 is great if you're willing to commit to going somewhere to pay and get it filled.
Electric is perfect for 99% of people, honestly. You'll just have to wait a little longer for tires to air up.
The route I went was by the 12 volt Shittybilt compressor. I highly recommend.
If I could do it all over again, I'd junk yard a York 210 and mount it in my jeep