Why not just GIVE her the 300ce "I love you so much I'm giving you my car!" and take over the '04 Camry. Sell it (the depreciation is horizontal so you'll get a good price out of it)

Then get yourself an E500. Admit it, you *know* you want one. But don't let her ever drive it. Not ever.

(Of course, that won't solve her complaint about you loving the 300ce more than her. It'd just gonna worse with the E500!! She'll rue the day you get an E500).

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1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...

1995 E 420, 170k "The Red Plum" (sold)

2015 BMW 535i xdrive awd Stage 1 DINAN, 6k, <----364 hp

1967 Mercury Cougar, 49k

2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive (sold)