New to metal cutting so need advice

Hi All
I’m new to metal cutting on the cnc router, (but not elsewhere as I have my own mill and lathe).
I have a part I made in MDF that’s stock size is 1.8" long by .625" wide and .5" high. I used a 2 flute, 1/16" HSS end mill with a 5/8" cutting length and an 1/8" shaft. The part came out great. I made a second .nc file in MeshCAM for brass. The MDF file was a total of about 40 minutes and the brass file is 4 hours. So MeshCAM definitely slowed things way down for the bit to work in brass.
Is it your experience that MeshCAM’s auto calculated settings for metal are good or would you slow things down further?
I ask because I snapped the bit just a few seconds into the job.