Do more digging. You can likely find 100 threads here about people with problems with that V6 transmission, and I'd say 50-100 about the SOHC V6. That's a huge number to find on just this forum, that is not all that exist in the world.
Keep in mind that the Explorer is one of the best, if not THE best, selling SUV's on the market. The SOHC motor is in a large percentage of those. That means there is a countless number of SOHC's out there. I'm going to guess that members on this board represent a small minority of those. So, 100 posts from people on this board who have had problems with their truck does not tell me that mine is a ticking time bomb.
I deliver mail for a living, I know brakes and transmissions, not to mention Ford engines and taking good care of it all.
You've stated you deliver mail for a living. That kind of stop and go driving is notoriously hard on a vehicle. I'm not going to deny that there have been issues with the timing chain and transmissions on some of the model years, but that doesn't guarantee that this is going to happen to every single one. Your experience is definitley valuable as you put your vehicles through harsh condtions which basically test it out in a manner that is outside the realm of the normal daily driver. But, because it's not the norm, it doesn't make sense to say, based on your handful of vehicles vs the many many more on the road, that every single one is going to live a short life and then blow up. I have also owned a few explorers, all with the 4.0 sohc. I am selling my 98 today with 90k miles. No timing chain noise. No transmission problems. Lots of towing. Could it blow up next week? Sure. Is it exhibiting any signs that that is going to happen? No. Any used vehicle purchase is a risk. It is up to the buyer to check that vehicle out until they are comfortable with the condition for the price they are paying.
I would pay $1000 more for the V8 truck, or more specifically not buy the V6 unless I had to.
For some of us, such as myself, "just pay the extra $1000 and find a v8" is not an option. I'm on a budget. This is why I'm buying a used vehicle instead of a new one. I don't have an extra $1000 in change laying around between the seat cushions.
I would have no problems, and I am actually planning on, buying another SOHC. A 2002! GASP! Once again, could it blow up? Sure. Is it showing any signs of that now? No. Based on my experience, it's a risk I'm willing to take for the money I have to spend.