I think the LS motor have the double swap, it improves cooling and the harmonics are less. If i recall Warren Johnson was messing the swaps to improve the cooling on his prostock vehicles, there's supposed to be some HP advantage due to the cooler running of the cylinders and for sure the less harmonics will help the engine last longer. I've never ran a 4/7 swap cam but i do have one in my 434" motor that's going in my Malibu.
JMO
Zip.