I am not sure what your application is but I would figure around 100 to 150 sfm.
If you are moving alot of material I would suggest Plunge Milling first with an Indexable tool, then you can run around there quickly to cut off the scallops.
I am not trying to push, but for the money a 1" Carboloy Seco Superturbo would be the best bang for your buck, I love them.
Big solid carbide endmills are expensive whereas indexable tools are cheaper to run.
I got introduced to them a couple years ago at a different shop and am still using them in the present shop I work in.
When you buy the body of the tool I think it's something like $100 to $150 dollars and the inserts are somewhere about $150 a box of 10. The body will last a long time (if you don't blow it up). So this breaks down to $15 per insert. The 1" uses three inserts that can be flipped, for you are basically using $7.50 per insert side x3 = $22.50.
The nice thing in the shop I work for, we use the same brand indexable from 2" to 7/8", all with the same insert. So we save our inserts that needed to be changed for finishing operations and use them when we are just roughing. In a sense, all of our roughing operations have no tooling costs because they are used and were basically paid for on our finishing operations.
The cool thing about the Seco is the "Speed Factor". Call a Carboloy Rep and ask about it. Right now I am running some toolpathes on a 1018 part at S5500 RPM and 150 inch/min. It's cool to see chips flying off like that with steel. Also, Carboloy has a 24 hr. tech line. You can call and ask questions for speeds and feeds.
Mike in MN