I have an Akrapovic Slip-on and am wondering what the opinions are for either the arrow or Bodis options.

I have fitted the Bodis decat with the Akrapovic slip on silencer and I have to say it is the best option if, like me, you don't want to buy the full Akrapovic system.
The Arrow is just a short straight pipe with a bit of a resonator in it but the Bodis is longer with a "U" bend in it. I am sure the length is important to the flow of gases.