And for that matter what a weld "looks" like is more about the skill of the welder, or even simply his style. There are a MILLION and one different circomstances where you can have a .35 welded part and it would look EXACTLY like a .23 welded part. Depending on weld speed and heat and material being welded. There is just simply no "look" between the different wires that would be carved in stone.
It is more about a "feel" that YOU will have if you switch wires. This of course will go along with a visual difference possibly, and of course a weld test where you break the part in to using a vice and a hammer to see how your weld held up.
Brian