I know you might be jumping about with glee, but remember… the SWTOR mouse is not the only one on the market with the 12-button grid on the side. Both the Naga and the Naga Epic do too. And I know from beta that the Naga works fine, and there’s no reason to think the Naga Epic would be any different.
So, as much as you like the imperial logo, I’d advise looking at pictures of all 3 of these, and deciding which looks most comfortable for you. After all, you won’t see the logo with your hand over it. At first glance, it appears that the SWTOR mouse has grid buttons that are more raised and defined, while the Nagas have a flatter grid area. This is ultimately personal preference. Also, do you like a corded mouse or a cordless? Naga is corded while the Naga Epic and SWTOR Mouse are both cordless.
You can always use a sticker for your logo of choice. Pick which mouse will work for you.