My most common metric bits are 3mm, 6mm, 10mm straight cutters the 6 and 10mm with and without bearing, also 10mm and 12mm end cutters.
This Australian link exports to the USA, where the current rate of exchange favours you in the US, they do sell quality cutters. As far as upcut spiral bits goes, I haven't been able to locate any so for dowelling, I use 1/4" and get the dowels from America!
My most used template guides are 20mm, 25mm, 30mm, 35mm and 40mm. I have many others that are only seldom used. For dovetails, I have to use a 1/2" (I'm very versatile!)
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