Well, for a desktop machine…carbide is carbide…Made in China or Made in Germany…same stuff for us…but a poor grinding (sharpening) job is more likely from China…but China also makes some awesome cutters too.
Now to practice…would you be interested in making your own cutter? A search here will reveal a REALLY EASY way to make (my name and thread milling search terms) using a 1/4-20 four-flute tap. Own a grinder? (Or a Dremel)…that all you need. It’s also the perfect size for a M6 thread. (All you need to do is remove (grind) all the teeth of the tap off except ONE tooth. I say to use a four-flute because it gives you at least tries at this easy DIY cutter.
FYI: A 1/4-tap fits into a 1/4" collet
If I can’t convince you to make your own, that fine one on eBay/Amazon for $35 ish
PS: I made a thread mill a few weeks ago out of an old (dull) 3/8- two-flute end mill. Worked AWESOME. They don’t need to be pretty to work.
(I’ll try to find some links)…while you ponder…
Link 1:
Link 2: Same as above, just scroll down to see the 2 YEARS LATER Stuff (which is from earlier this year)