We have had very good luck with these: http://www.2linc.com/engraving_tools.htm We have mostly used these for an application where we are machining serrations into H900 17-4, and not much else works at all. We have used them for aluminum as well though (the aluminum specific ones..). The gear spindle speeders warm up like crazy (we bought a Nikken), so running them is not fun. We have a really long warmup cycle before we even try. The cutting depth drops about .004" from cold to warm. Coolant thru speeders are much better about warmup, but only if you have the setup for it obviously.

We use both Sterling and DME. We like them both and check both every time we need gun drills.

^*ranty [auto correct, shouldn't be posting from my phone]

We have two Kitamuras with the new Arumatik-Mi controls, and they may turn us away from the brand. Horrible decision in my view to put a fanuc-ish front on the Mitsubishi control. The control has a slow feel(button response) and has a quirks that seem to stem from its false front. I could get really rants on this topic actually. I personally have many many hours working through issues that come up, and they just don't happen on our fanuc or haas controls. Technical help is a challenge as well, because you have to consult the kitamura books for some stuff, and the Mitsubishi books for other things. Not everything in the Mitsubishi manuals applies, because the control is trying to act like a fanuc! Really frustrating.