My car still rumbles the house in the morning with it removed, screen door rattles, pictures/dishes shake, etc. Theres still plenty of grunt on startup. I mainly did it to lower the amount of car alarms I set off.
I don't want to turn this into an exhaust thread, but this car reallly sounds better without cats. I have hfcs and straight pipes for my xpipe, there is so much more deep bass and volume without cats (paired with an agressive rear exhaust). It just doesn't sound loud, it sounds good. The sound is night and day imo. My hfcs have almost a tinny sound in comparison, especially on startup, and I loved that setup when it was on my car. Cold start for me makes the car feel more artifical than it needs to be and actually annoyed me.
Melbourne Red E92 M3 DCT Sparco CF/Alcantara DTM Seats.KW3 Coilovers.Apex Wheels.OEM Performance Spoiler with CRT Theme & Splitters.Turner Subframe Mounts.Vorshlag Camber Plates.RD Sway Bars.AD08s 265/295.15 lb. Braille Battery.Catless Gintani Race.ESS Tune.Dinan Pulley.MS2 Intake.100 Octane Mix.Schroth Harnesses.Challenge Harness Bar in MR.Challenge Toe Link.Krics R40.Turner Studs/Pedals.SS Lines.Rear Seat Delete & more I can't remember