Tekken Tag 2 has the one of the most outstanding netcodes for online fighting games, it is probably one of the leading ones out there. SCV is what started the good connection experience...
Pig Of The Hut
I disagree with this, 3d games are much harder to program since it is on a much more diversified dynamic playing field and there is allot of data flowing where as 2D fields only have two movement of directions and data feed from the background. At any fault, it would be the companys use of there networking capabilities.