I'll give you the easy solution to picking the right insert..
And it won't fry your brains, and it won't take
a doctoral thesis to understand.
Pick up the phone and call Curtis(ExKenna on this site) and say
"Hey Curtis, I need an APKT 1604 that does XXX and YYYY and ZZZZ"
Then it shows up on my door step, and does XXX and YYYY and ZZZZ..
There are people that do this for a living. Also every cutting tool
you've ever bought, a little bit of that money you've spent is used
to have tech people on staff that know this stuff..
I haven't chosen an insert out of a catalog for myself in probably
10 years.. I know what basic edge prep I want, light hone, medium
hone, dead sharp etc.. I know when I want it really high positive and
when I don't.. I know when I need an aggressive chip breaker, and when
I don't... What I don't know how to do is to transfer that knowledge
into a big giant long code to get the insert I want..
Then nevermind the coating and substrate and how that works with your
insert geometry... That is way over my paygrade.. And there are people
that know this stuff inside and out, and they only charge you money
if you buy stuff from them..
Just my 2 cents on the subject. I have more important stuff to do
(like play on PM) than digging through a catalog trying to figure
out what insert I need to buy.