it's all about personal preference. Some people like the extra contrast with metal azo, but for me, I don't really enjoy it all too much.
Here's also another labeling tip with T@2, before you burn, go to preview, and then do an invert. What this'll do is invert the the invert color scheme. The reason for this is that, if you don't know, you'll see about a 1 to 2mm empty space between the actual data and where it starts burning the image. I couldn't stand that ring so I always burn inverted.