The Phillips 78 (or are they Filarc 78) are 7018s that contain 1%Ni to improve the sub zero toughness. They are very good rods but they are lo Hys so not the easiest to use.
Ive no idea what the Weldrite 44 are.....if my memory serves me well Weldrite rods were or are rebranded. Is there any info on the label?
The "universal" rod for hobby welding mild steel is a 6013, preferably a premium brand 6013 (George B will not agree). These are easy to use and are perfectly fine for welding garden gates etc but if your planning a nuclear sub you may need something else.