Im good at Arc (did it for 5 years doing fab work) im still fairly new to mig... havn't even touched tig yet.. Havn't layed down a strength bead on the rig yet with mig.. when i built it I mainly used arc with 5P and some 7018 over it...
only mig i've really done is my half doors which doesnt need to hold any kind of strength.. it wasn't easy on 18 gauge.