my favorite is by far tig on stainless and mild steel i like aluminum if i am not being rushed but its still kinda a pain to me, i like mig good all around welder the spool gun makes welding aluminum alot less time consuming than tig welding it and oxy and arc are about even i used to be realy good at oxy and arc but havent used eather in a wile
for arc and mig i prefer lincoln machines and on tig i prefer millers