Originally Posted by
louieatienza
Buy them as you need them, and buy spares of each one to minimize downtime. Compression spirals for panels; the faster your machine can cut and the more HP your spindle has, the more flutes you can use. I like Onsrud tools. Insert V tooling from Amana is great, since you get two edges from each insert, and they can be honed in a pinch if needed. You also don't have to remove the tool to change the insert which is a good thing should one break or go dull in the middle of a job.
I'd hold off on 3D cutting tools until you really need them, because some 3D jobs will require a tapered ball endmill, and some can use a larger core box or ball nose bit.