I was looking at putting some BBS RC's on my 99 M3 but I cant decide whether to pay the extra $ for the RCJ's which are forged or just go with the regular RC's. I heard that the regular RC's are very soft and might bend easily. But I also dont know if I can fit a 9" wide wheel in the rear without modifications. I have the H&R Race with Bilsteins. please help with some opinions.

Regular RC's are fairly strong actually, like pretty much all BBS wheels. But they're only as strong as the next wheel when you go running over potholes and curbs...

Yes, you can fit 9" wheels out back, but with some modifacations probably depending your tire sizes......you should get your fenders rolled just in case...

Preppy is correct. There is no BBS wheel that is soft. They all exceed TUV standards for strength and durability. The 9" wide wheel wouldn't be a problem for the rear as long as you stay conservative with the tires.
If I can help let me know.

BBS is my favorite wheel manufacturer. Good choice on wheels.