I dont want to splice into any wires so the power wires at the mirror is no good for me.If you are installing a dash cam then you might consider just tapping into the power wires at the mirror.
If you add a fuse then yes, you need the mini-fuse version. You will want to connect a relay that will disconnect the power once the ignition is turned off.
I rather not splice any wires for many reasons. I rather just use Add-A-Fuse but not sure which fuse slot is the best option.Tapping into a wire with power up top near the mirror and sunroof stuff is the best option. That is no problem using one of those wires. Plus, you don't have to remove the trim around the A pillar to run the wire. There is an airbag there and it is tricky.