I'd pay full price for an MPE than put on a free akra someone gave me.
All the other exhaust systems out there take away the already unique sound the M3 has. The MPE amplifies it and changes it into a more unique sound. Plus weight savings of over 20 lbs with Inconel. No brainer if you ask me. And none of these slip ons are going to give you anything noticeable in hp gains so choose on sound first, then looks, then price, tho I wouldn't let cost compromise my top choice.
Not to hijack, but we do have to cut off the back section with a saw to install a slip on correct?