Thinking about buying mac axle-back exhaust for 4.6. I've seen mixed reviews so not sure what to do. Any suggestions would be appreciated

 

Don't know a lot about those Macs. I hear they sound great, but I also heard there's interior drone around 1800-2000 rpm which can be annoying. If you are concerned about that, then go with something else. Me, I have the Ford Racing axle-back GTAs and they sound better and a little louder than stock. I can really hear it roar when I hit the gas, but there is no interior drone at low RPM.
On the other hand, if you don't mind the drone then go for it.