Release 1.12 Requires a GPS Change but unsure which ones

Here is the GPS full release about the v1.12.0, " The GPS protocol now defaults to u-blox for faster startup, and GPS_x_PROTOCOL needs to be changed if another GPS is used."

In the QGC parameters under the GPS_1_PROTOCOL there are 6 options:

  • Auto detect
  • u-blox
  • MTK
  • Ashtech / Trimble
  • Emlid Reach
  • Femtomes

My 2 questions are:

What does each option mean?

If I use the GPS Module (with compass) M8N, which option would work best?