i just have to point out some facts here:

-goblin eng can make gnomish cloaking device

-There are more items which only goblin can make (these are not labeled "goblin" but u can only learn them from the goblin eng trainer) eg. The big/bigger one and sapper charges

-most gnomish items have a chance to backfire

-Goblin rocket launcher!! 45stam, heaps of damage (which can crit), 45 yd range! 45!!! turning some1 into a chicken aint gonna match that