Basically, you want to take the biggest depth of cut you can, still maintaining good results. You'll have to experiment with this to find the optimal roughing depth of cut that works for you.
The end mills you found should do, but see if you can get single flute end mills. Make sure the end mills you get are not coated - pretty obvious for a single flute end mill as it is designed for cutting plastics, but far not obvious for a 2 flute end mill.
Daniel