Ive shot them with both. The only suggestion I can make is dont go to big on a cutting area, and dont put either in the shield. I have had equal luck with both. I shota couplethis year with nap shock waves with no problem. I also shot a few this year with Muzzy three blads, with the same effect. Here are some pics of deer hearts I shot with both fixed and mechanicals this year. Both were shot with the same bow at about the same distance.
This is a heart at 35 yards with a muzzy three blade 100 grain.
Here is a heart shot at 30+ yard with a nap shockwave 100 grain.
There was not a whole lot of difference. Both passed through about the same, and the deers both ran about the same distance. Blood trail about the same, Entrance and exit wond same on both animals.