Hi Gburg -
I am sure there are many other excellent and likely better engine choices out there. I am not going to address that. You asked about two specific motors and I happen to have first hand experience with exactly (and only) those two motors, so here's my .02
First - Cobra Ed - you've got your compnent description just backwards between the Ford and the Roush engines - a typo, I'm sure.
Second - I have owned and run both of these motors - hard. Not abusively - just hard.
My spf originally had a Ford Racing 392 stroker. I put 30,000 hard street and track miles on this engine before I feathered the throttle a little too much for a little too long on the backstretch at Carolina Motorsports Park. The engine went lean, the hyper pistons went into melt down and the engine totally grenaded. Basically my fault - but I would never own another engine with hypereuratic pistons. Ford of course has figured this out as well, and they now put forged pistons in the 392s. The Ford racing motors are built with good (not the best) components in an assembly line fashion by experienced assemblers that I choose to believe take some pride in their work. I think the Ford Racing engines offer great value. BUT, they are definitely built to a price. When the engine was putting out it's max, it always felt like it was doing just that - maxed out.
When I replaced the 392 I was looking for more horsepower and better quality. I looked at lots of options had narrowed it down to Roush, Keith Craft and a custom NASCAR builder in NC. It so happens that my spf dealer had a customer back out on a Roush 427R and my dealer had it sitting on his shop floor and he wanted it gone. He offered me a "good" price and that was that. I do not regret going with the Roush for a moment. There is really NO comparisson between the Roush motors and the Ford Racing motors. The Roush motors are built to be the best they can be and you will pay a premium price. The block is a DART 4 bolt main, siamese bore, 9.5" deck height full on racing block rated to withstand nearly THREE times the horsepower and torque my engine produces. This goes right down the line for every component used in this engine - crank, rods, pistons, timing chain, ratarata. The word is OVER BUILT. This engine produces it's (substantial) rated output power and never comes close to straining to do so. It is SNOOZING while it launches me down the dragstrip in mid 11s on street tires! I get the feeling it can do this for a VERY LONG time, and will eventually die from old age - NOT fatigue or over stress.
...and that's the perspective from the driver's seat of my car.
Happy Motoring!
-Steve
Richmond/VA