what is the lowest power by tig?(i mean how many amper minimum) most of those cheap welders wok up to 20 A,which may be annoying,if you want weld thin stuff. though i buyed a chinese tig,it welds on 5 amp ,and it really welds all day,even at 160.only problem the torch is getting too hot to use... though the unit was ~300$,but if i had the money,i'd buy the merkle(3000$). life makes the decision easy...