Carbide works fine for flycutting, both inserts, and roundstock. And isnt to brittle. I use both. Mostly cause i find carbide makes a better surface finish one some materials than HSS do.
Just because something were intended for one type of tooling doesnt mean its still the "best" solution. Sure it gets the work done and sure its easy to handle. But i rather no resharpen the HSS bit like 10x times for one lengthy operation. When i can use a carbide that more or less works faster and produces a better result.
And i use Cobolt reinforced drills for drilling. Not pure HSS drills, cause i really hate resharpen tools all the time.
For interupted cuts with carbides ive found they hold together better than hss tooling that gets dull really fast when doing interupted cuts. Maybe its just me i dont know - im learning as i go and trying to take note on what happens with my tools (mostly cause im a cheapskate and hate buying new ones all the time.)
What im trying to say is: Pick the right tool for the job at hand, there is nothing really right or wrong. Most tools are developed for a reason. If it fits your need and its what you have learned and know.. use that then.
The insert on the TCT flycutter is really cheap and readily available from multiple manufacturers as well, i usually buy those triangles in bulk from china. U get like a 100 of them for the same price u get 5 HSS blanks (aliexpress.com is the way to go, they show up and disappear now and then). And add onto that the fact new HSS blanks arent same quality as they were 15 years ago. I got some old HSS from a member on this board, and i love em. I got some new as well and they are used as distance blocks mostly cause they cant hold an edge at all
