had 275/30R19's on my M3 with BBS forged wheels.

Handling was amazing, but it was a harsher ride. I never bent a wheel nor popped a tire in a pothole driving 3 years in SE michigan (horrible roads). I bottomed out many times, but having very strong wheels help tremendously!

Remember that 30 is the % of the tire width, so if the tire is wide, it would be similar to a thinner tire with a higher aspect ratio.

i.e. 275/30 is around the same as a 255/35

if the tire was a 225/30, then that's a different story.