I have a '97 SOHC 4x4 Explorer Sport and also owned a '94 2WD OHV 4.0L Ranger so I can tell you my experiences with both. I also have the Owner's guide from my Explorer so I can tell you what the different motors were rated at. In 1997 the OHV was rated at 160 HP at 4200 RPM whereas the SOHC was rated at 205 HP at 5000 RPM. The OHV was rated at 225 ft/lbs of torque at 2800 RPM while the SOHC was rated at 250 ft/lbs at 3000 RPM. I woudn't consider a 10% increase in torque fairly equal. The only thing fairly equal is the torque peak. They are only 200 RPM apart for both engines.
What does that mean performance wise in real world driving experiences? I have ran both my Ranger and my Explorer in the 1/4 mile when they were stock. I also ran my Ranger in the 1/4 mile after adding a Pro-Flow MAF sensor, Exhaust Tech cat-back exhaust, K&N drop in filter and opened airbox. Both vehicles had the highest ratio limited slip offered (Ranger = 3.55 & 26" tires, Explorer 4.10 & 30" tires). My Ranger had a 5-speed manual, my Explorer has a 5-speed automatic. Stock for Stock, my Explorer gets to the 60' quicker than my Ranger did by .05 seconds and that is with the added weight of the 4x4 and SUV body/seats. My Explorer completes the 1/4 mile .449 seconds quicker than my Ranger did. Once I put my cat-back on my Ranger, my 60' times dropped to .117 seconds quicker than my Explorer, but my 1/4 miles time was still never closer than .183 seconds to my Explorers. My Ranger felt like it took off quicker due to the manual transmission, however my Explorer more than made up for it within 60' and pulled stronger for a longer amount of time.
Reliability wise, I only had my Ranger for about two years & 24K miles. In the two years I owned it, the only thing that went wrong with it was my O2 sensor. As a matter of fact when I picked it up from the dealer after they replaced my O2 sensor, I spotted a '95 T-bird that I wanted. A week later I made the trade. Anyway, my Explorer has 89K miles on it and has had far more problems with it. All of the problems have been fixed and everything that did have problems has had the warranty extended by Ford on them. The only things engine wise that has gone wrong with my SOHC are the throttle body sticking, lower intake manifold o-rings leaking and the camshaft tensioners rattling. Now that I have had the latest revisions of these parts installed for the last 16 months, I have not had one problem with it in the 25K miles that I have put on it since. 86K miles on it and it still pulls as strong as new and gets the same mileage (16 city, 19 highway). If you look at a SOHC, just be sure that the miles are less than 72K miles or that the latest updates have been performed and the engine shouldn't give you any troubles. There will always be some that will fail from every model, the OHV and the SOHC are no exception.