To be honest they both felt about the same. However the akra evo with the tune was night and day different and a lot more fun to drive. To be fair though I didn't have a tune when I ran the MRF so in that aspect I can't compare.
Most full exhaust systems are going to basically have the same power, just comes down to what sound you like the best and also the weight.
All I can say is the akra evo + ESS tune to me was a great choice, and I was happy I made it.