I had the mat in my E46, and just got the e92 mat in my, well, e92. It's a good fit and easily as good as the e46 style. In fact I really like the higher sides for spill control, but there are cutting guides on it should you want to use the full width of the trunk.
One thing I do like better is the material is grippy, almost sticky, so stuff stays put, especially as I also have the luggage net in there to keep stuff from becoming a physics lesson while I drive in a spirited manner...
2010 E92 M3, DCT, w/Exhaust mod
2002 E36/7 Z3 2.2 Sport
2016 F22 M235i Coupe, MW, ZF8
On Order for Week 2 2017: 2017 M2, MG, DCT