It's a debate that goes on. Failures many years ago scare people, but I tend to believe assembly methods or subpar parts could be some of that blame. Nowadays not much worry, and the big 3 are still using floating pistons in some engines today.
There is balance weight to consider, and the fact that the pin isn't stuck in one position while the engine runs. Some arguments made that floating pins are beneficial for short stroke engines, some say frictional gains, and many more reasons. Pros and Cons with both. The machine shop I used does dozens of high end racing engines every year that make well over 1,000 hp, and he makes your head spin with knowledge. When we discussed the issue, by the time we were done I was comfortable with the choice. Plus, that's the way 69's were and I liked the idea of keeping it that way.
Excellent machine work goes a long way here too. I bought new Eagle rods and he made sure he checked and "tweaked" each rod and piston pin to make sure clearance was spot on. Even the big ends of the rods were also "tweaked" for proper bearing crush. Pistons call for .002" to .0025 side wall clearance so they run very tight in the bore as well. That's snug for a forged piston. Not only does that make them very quiet, but you also gain better ring control which means better compression and oil control. Sloppy pistons cause all kinds of oil consumption and ring flutter issues.
Lots and lots of details went into this build looking for HP as well as longevity while keeping things stock, or stock appearing, including coatings where applicable and other tricks that are trade secrets with these engine builders I'm not even aware of.
