yeah the welds are fine definatly tig (they were welded by hand), i will tell better once mine arrives next monday as for the penetration, porosity, and stuff. When it comes to tig there are different ways to do it, they could have overlapped the melt pools more and given it that "row of coins" look but that is done in a continuous weld, i'm betting to keep the tube from stressing and warping it was kind of a spot of weld here spot of weld there thing to keep the heat even. like i said we'll see when it gets here but in my opinion so long as they used the right rod and the right gas and the welds don't rot out or leak it'll do. the only people under my car other than me will be peds i accidentally mow over and i don't think he's gonna have to good of a look at the welds if he fit under a 3" ground clearance car
Edit: after a fourth and fifth look at the photo i'm willing to say that the welds do look strong enough you don't want the weld to bulge out to much more past flat between the outer boundary of the pool so it looks like they used enough filler