If you're really interested in the handling aspect, spend the money and get the adaptive drive. Drive one with and one without to decide if it's worth it. I haven't driven either yet, but I'm guessing they're worlds apart and I'm also guessing you'll be amazed by adaptive drive.

If you do end up getting a non-sport model, I think you will in-fact not experience the same level of stiff ride if you just add 19's. If the handling is not that important to you, then I'm guessing you'll be happy with this choice.

Not sure what the sport button does on a non-sport. Are you sure it's there on a non-sport?

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'08 335i Coupe - Barbera Red / Saddle Leather / Light Poplar Wood / 6spd Manual
Options: Sport, Premium, Cold Weather, Comfort Access, Active Steering (awesome!), Power Rear Shade, IPod Adapter, Navigation w/IDrive
Mods: M6 Wheels, Split Armrest, M-Steering Wheel, Euro Light Switch w/Rear Fog Lights, Short Shift Knob w/Matching E-Brake Handle, Clear Reflectors, CDV, Clear Bra

Retired:'04 X5 4.4i