From my POV having owned 3 Duratec/CD4E mystiques:
Pros:-Attractive exterior even almost a decade after it was relaeased
-Pretty decent power from non-SVT Duratec
-Engine will sound AMAZING with cheap exhaust upgrades (SVT stainless quasi-dual)
-Many SVT goodies will transfer over without too much drama
-Not a lot of aftermarket...which forces you to make your own parts...which makes most mods unique
-CEG...massive database for info/fixes/maintenance ...it really is a valuable asset to owners
-Tight handling...with upgrades from BAT and others the car really feels solid and gives you a lot of confidence
-Mystiques have some little extras here and there (wood type dash if you're into it, several extra courtesy lamps over the rear seats and in the front doors, driver side glove box, different design for rear tails and reflector which looks great imo)
-very fun cars when they work right...cheap too
Cons:-CD4E...all of it...the whole damn thing
-Engine bay is very tight which makes it a PITA to work on
-Sunroof gear. Seems the aftermarket gears haven't stood up to well either
-Dash warp
-Stock fogs on the mystique are terrible all that i've seen have been cracked and as a result water seeping in blows bulbs
-Stock headlights haze over really bad, coating on the lense does not stand up too well to the environemnt...and unlike contour lamps, discounts on mystique units are not as big
-Alternator PITA to get to for duratecs
-Not a lot of aftermarket
My posts are sometimes stupid 
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