Factory 3.73's on my 14 GT/CS and they whined until around 6,000 miles then stopped. However, 3.73's in our cars tend to whine, and trust me, no amount of whine is worth the small amount of pull you might feel on the low end. I agree that 3.55's is the sweet spot for our 11-14 Stangs! With that said, I'd leave the gearing alone unless you have those nasty factory 2.73's.
"May the Force be with you always!"
2014 Mustang GT Coupe Premium. Options include: California Special package, comfort package, navigation, glass roof, shaker pro system, 3.73 ratio limited slip axle, GT front grill/fogs, MGW race spec shifter, BBK X-Pipe, Corsa GT500 Quad Sport axle-back, Ford Racing ProCal tune. "If I wanted insane HP, I would have purchased a 2014 Shelby GT500!"