I had JL's type 2 rep diffuser. I found the fitment to be only so-so.
There were gaps between the bumper and the diffuser that I found unacceptable. I got a type I diffuser (authentic VRS) from a forum member here and the difference in the fitment was night and day.
Just my experience.
2009 E92 M3 Le Mans Blau on Schwartz. DCT, EDC, TECH PKG, M Drive. RAC RG63 19x9f ET22 19x10r ET22, Yokohama Advan Neova AD08 265 30R19f 295 30R19r, Ground Control Coilover Conversion, Eisenmann Race Exhaust.