I bought the 135i because I came from owning a string of VW GTIs, and I wanted something that was significantly better in all performance aspects. The 135i fit the bill.
His: 2013 ///M3 - Interlagos Blue Black M-DCT
Hers: 2013 X3 28i - N20 Mineral Silver / Sand Beige / Premium, Tech
Past: 2010 135i - TiAg Coral Red 6MT ///M-Sport