I have several of both and can't really tell based on that alone...and I can say that because I have traded shafts between some them that are otherwise extremely similar.
In fact, I have two versions of exactly the same cue, one with a brass joint and one with SS. That example happens to be a pair of early Adam cues. The earlier version has brass, the later one is SS, but they are otherwise the same. They feel/play identical with the same shaft.
One has a bumper and the other does not. I find that does in fact make a difference in the feel of the hit. It does not change how the cue plays, but the sound and feel is different. If I remove the bumper then the two feel/sound virtually identical with the same shaft.
I am confident that there is a difference since they are different materials with different mass, density, resonance, etc. But I feel the difference is probably beyond the resolution of my own sensations.