I used to drill my PCBs using a normal, heavy driller (I guess that's why the mm tick bits usually didnt last too long ;)). I had a Dremel but I didn't use it for that, because I was used to the heavier driller.
Then one day I saw this "Dremel Work Station" on sale, which is basically a drill press with a few extra features. Dremel's ads are always mentioning the excelent precision of their tools, and I thought that would be handy for PCB drilling. So I bought one.
Well, I must say that it was rather disappointing, at least for the price (~60euros). The press has a lag of maybe 1-2 mm, which seems little but is enough for you to drill completely out of the spot. When the rotating bit starts touching the PCB, the rotation makes the Dremel deviate 1-2mm (the lag) to one side, and you drill in the wrong place.
I wanted to return it to the store, but I still needed a simpler way of drilling... then an idea came to my mind. If the press always deviates to the side, then let's make the deviation permanent! The fix was easy; just attach a rubber-band! It pushes the Dremel body against the press's arm, completely removing the lag. You should attach a strong one or several of the "normal", weaker ones (as I did).