Definetly the MK 23, if only because it's so incredibly cool. Also, it's more practical than the Desert Eagle. Maybe you wouldn't use it for concealed carry, but it's make a badass HD weapon.
plus, if state law allows and you wanna jump through hoops to get ready for the circus you can get the suppressor for it. THAT would scare the bejeebers outta someone on the wrong end...