I compared the Steel City and Delta benchtop mortisers the other day, and was shocked at the similarity between the two machines. Same motor, same switch, same features on the frame (support and adjustment), same lever mechanism, same same same. It really looks like a lot of the parts came from the same factory! The Steel City had a couple extra features like outfeed support extensions and adjustable dogs to retain the workpiece. One turnoff was a clear flimsy plastic door that conceals the chuck, as opposed to the Delta's metal door. The price was $70'ish more for the Steel City, so I opted for the Delta.
I've looked at some of their other tools and have been very impressed.