If your indecisive coworker has to have a slushbox, I'd go with the IS350.
However, for about the same money, a used E39 M5 has a lot more class and much larger cojones than any of the cars yuppie boy is interested in. I'll take mine in Le Mans Blue Metallic with black leather and the 6-speed manual, please.
+ a zillion, except I'll take mine in black
"Racing makes heroin addiction look like a vague longing for something salty" - Peter Egan