Although I am not a professional welder I have done plenty of it in my life for personal use and in some cases stuck things together for others. I took a course taught by the local community college and learned the ropes with a TIG machine. In my opinion that first welding job was done by someone that knew their way around a TIG machine but being human and probably on a time schedule could only do so much, the second set was probably done by a robot with a tig machine, as such is probably superior to the first weld, deep penetration with a TIG machine is not as important as consistency, deep penetration can result in weakening the surrounding metal, it will fail before the weld does. You want that balance that in my opinion looks more like the second weld. One of the first TIG welded things I saw was a bicycle frame that was made from polished aluminum tubing, it was a $1.5K dollar bike back in the 80's and looked like something the Terminator would ride. All of the welds looked like a stack of dimes laid over, it was beautiful and peaked my interest in TIG welding which to my mind is more of an art form than any other type of welding, I've seen some creative stuff done with stick, and heli-arc but never anything that approaches the structural beauty of TIG. Just a layman's opinion...I have a few friends that put their life's work behind a welding mask, they will argue about the work they did on nuclear power plants where every weld was x-rayed and it was done with stick.