For me it would hinge on the definition of "good cosmetic condition". If you have a plywood cabinet from Japan, and the there's seriously nothing but a few minor scratches, then I'd value it subtantially higher in my mind.
Usually, someone says "good condition" and that means the bottom and back edges of the cab have significant amounts of paint chipping, there are holes from security bars, the speaker grill and bottom edge of the front panel have chips, etc. Of course it looks great on a cell phone pic, but in reality it's pretty torn up.
The way I look at it, everything but the cabinet can be fairly easily replaced, making full restoration to a mint game pretty freaking painless IF the cabinet is in near mint condition. I mean, what's a new DK bezel cost? $35.00. That's no problem. It can be shipped and installed with only a few minutes of labor. New T-molding? Minimal cost and labor. On the other hand, if the t-moling, cp, bezel, marqee, monitor are all mint and the cabinet is beat to crap, that means you have to spend hours and hours restoring the cabinet, and you loose the original enamel paint job in the process. Fairly new T-Molding, side-art, and monitor cap kit add about $50.00 of value in my mind. You see tons of DKs where that's the case. You rareley see an unspoiled cabinet and in my mind it would add several hundred dollars to the value. I think $600 for a DK in a mint cabinet with a horrible bezel, cpo, and marquee, and a fucked up monitor is a really good deal.