420 SEL is 201HP VS the 560 SEC's 238 HP!
0-60 mid-eight secs VS 0-60 low sevens.
The 560SEL is a few 10ths of a second slower than an SEC. Not sure if the final drive is the same (?) More ponderous than the SEC, but still a competent performer for such beast. Imagine the 420 on steroids