MC402 vs. MC252 B&W 803S

Any comments as to how the Mcintosh 252 does with the 803S vs how the 402 does with those speakers? Will the 803S get damaged by running them loud with the 402 so long as the power guard does not come on? In other words, can the 803S take up to 400 watts ? I know the recommended amp is 50 to 250 Watts at 8 ohms but those speakers dip to 3 ohms at long freqs. Also heard that B&W recommends an amp that doubles output power for speaker impedance of 4 ohms. What ohm tap are you using on these speakers the 8 ohm or the 4 ohm. Any reason to go to the 402 or is the 252 plenty.