All the major companies make great bits for CNC use both Router type bits and End Mills.
Freud, Onsrude, Whiteside, CMT, Amana, Eagle America and more are in my shop. And the best bits are "almost" always the more expense bits.
I purchase my bits based on best for the application meaning price verse performance, not name brand. I find this out by researching what others have used and reading the reviews and what worked best for me over the years.