From personal experience, 2.5 td 5 series are only just quicker than walking!! (I drove one a whole 20 minutes ago )

But they are good top end - Had over 145 on the clock out of it (but the GPS confirms the clock is 10% out ) Done over 130 on the GPS no problem though! And it still feels like you are going 60mph!

But anyway, RX-8 would anihalate it without a shadow of a doubt! (5 series can't even keep with a Saxo VTS!)