Hmm, I've had nothing but good experiences and with cars in the US and Europe in more than 20+ years.

1977 320i (E21, US), sport Bilsteins (as the car was 1" lower). Firm but good.
1981 M535i (E12, Europe). Factory Bilsteins. Great car, firm but good.
1980 733i (E23, US). Aftermarket Bilstein HD / B6. Firmed it up nicely, made a large "boat" corner like a BMW should.
1990 325i touring (E30 touring). Aftermarket Bilstein HD / B6. Firmed it up nicely.
1995 525 touring (E34, US). Aftermarket Bilstein HD / B6. Firmed it up nicely.
2002 Honda CRV (US). Aftermarket Bilstein HD / B6. Did rear first, totally eliminated front to rear pitch. Front were the icing on the cake.
1981 320/6 (E12, Europe). Bilstein HD / B6. Firmed it up nicely.

The ONLY car I know that it can cause issues with is the classic BMW 2002, the B6 rears are WAY too firm. Front B6 are fine for this car however.