I could never pin point any mechanical differences. I've always noticed that the OBS feels like it handles better than a 2.5i but that's probably because of the wheels. The seat fabric is also a huge difference. The 2.5i has a very "grabby" fabric, so dirt and whatever else like to stick and stain. The OBS seems to have a much more rugged fabric that can take abrasion and clean up easily. That and I like the standard roof rack, colors, fog lamps, and heated seats that the OBS comes with.

 

obs is hideous, do yourself a favor and get the 2.5i

my .02

 

i would trade but i don't want to get the attention of an sti and i'm looking for super low miles.

The OBS is not hideous in black with the underguards removed!