I have an '88 ford 150 with a 300 I6. It has over 350K miles on it, and it don't burn a drop of oil, and it starts on the coldest of days. It's not without it's problems, as it has several major oil leaks. It was my daily driver for many years and only twice I've had to walk home while it sat broke down on the side of the road. Once was a failed timing gear, the other a failed ignition module. I don't drive it much any more. It hasn't been registered in five years. I use it to haul junk to the dump once in a while, and to haul my boat to the lake, that is just 5 miles from my house. I have nothing but good things to say about the ford 300 6, although I have heard from some that rebuilding them is not for novices.
On another hand, I used to have a '63 Chevy 1/2 ton with a 292 in it, and it was an awesome motor. I drove it for 2 years with a cracked block. Sometimes if it got a little hot it would blow a little steam out the crack, but never any real coolant loss or coolant in the oil. I never took it apart, and it ran fine when I sold it (yes, I told the buyer all about the cracked block and he was ok with it) I have nothing but fond memories of that motor.
On one other hand, I had a '71 Toyota Land Cruiser that had a Chevy 292 in it. Funny thing was, this motor was built by Toyota, in Japan, with metric bolts, but everything else was identical to the Chev., plus the Chevy parts were cheaper and easier to get. Things like the water pump, which Toyota wanted a hundred bucks for, the Chevy one fit just fine, for $19.95. Even the points I used were for the Chev. And that motor was always ready to go. I drove that thing all over the west for several years with never a single problem from the motor.
I think it comes down to personal prefrence between brands for the most part. They are all very good motors.
