Wow. Tool snobbery much? I mean I know we're all tool snobs and looking for the next gizmo to display in our toolboxes, but geez.

Dude, get a good, nice, new 2mm drillbit (I prefer those with a quick fit hex driver - I have a driver, plus it can be used by hand if need be) and drill from inside, then cut the burrs on the outside with a scalpel/hobby knife new blade around the base of the drill after it punched through. Withdraw the drill and voila! The perfect burr free hole. Any 2mm hex driver will go through that hole when it's lined up with the ball hex.

The drillbit itself can be used as a reamer after drilling the hole by pushing/pulling it through the hole without spinning. The very sharp edges of its cutting spiral do a great job, but it might drag some swarf inside the cup, so be careful.

That's it, job done with 2$ worth of drillbit!