I'm voting studs. The mini tanner is a great size and design, but I it looks better when's two colors or something else going on.
I love the studded and will likely pick one up with the recent 25% off coupon but think the plain is a better choice if your aim is a more timeless style. However, as a trend, studs have a kind of a bold, rocker chic timelessness...I mean, does rocker edge ever really go out of style? I say get both, because mini-Ts are mighty addictive.
Studded, you will have opportunities to get other mini tanners in non-studded options but this will probably be the only studded incarnation