I owned a Gen 1 for more than 8 years. There were many ups, and a few downs.
What I liked: Power, comfort, impressive and fun off road capability, massive cabin, nice options (mine was hard loaded), great seats. Didn't burn a drop of oil.
Irritations: Fuse 20 (I think), the power rear window switch failed (20 bucks and 15 mins to replace), the locker dial (pull to lock the diff) wore out and needed to be replaced, that was another 30 bucks and 20 mins to fix.
The only serious mechanical failure was the output speed sensor on the vehicle's transmission lead frame. When it failed, the truck would intermittently stall. As I recall, it was $900 or so dollars to repair at my local shop. Sadly for me, Ford would've fixed it, via recall, a month later. And because I didn't get it fixed at the dealer, FMC refused to reimburse me. The last issue was the AC. I live in Dallas and use the AC approximately 10 months out of the year. When I traded the truck last month, I was on my third compressor, which cost approximately 1k per instance. The truck had 98k miles on the clock when I traded it in.
If you buy a Gen 1, it will likely be a rewarding experience. There wasn't a day that passed where I regretted owning my Gen 1. If you decide to buy a Gen 1, I'm sure you will find a post or two on this forum about what to look for when you're in Gen 1 market. From my experience, make sure the shocks aren't leaking, verify the truck bed gaps are even with the cab (if not: likely frame damage), look over all of the the power equipment, including the rear defroster, and make sure you put the truck in 4WD: Both 4 high and 4 low. A word of caution: torque steer is evident when the truck is in 4WD, it's horrible. The 6.2L V8 sounded great, and after 8+ years and two newer generations of Raptors, the truck still got complimented regularly. Lastly, I averaged 10.2 MPG combined on factory recommended 87 octane. No leaks, no squeaks, no rattles. She was a good truck. Certainly one of the best I've owned over the last 35 years.