Moley,
You are doing 'Apples and Oranges' here; you have two large-diaphragm mics here (102 and 103) and a small-diaphragm (184.)
The first two could be used for vocals; the 184 is really made for instruments such as acoustic guitar, percussion, or perhaps as overhead drum mics.
I have no experience with the 102, so I'll address the other two.
For what it's worth, a colleague uses the 103 for vocals, narration and guitar cab amping and he loves it; I imagine it could be a good all-round budget condenser for you, vocals and horns, plus as a spot mic. I have heard voice recordings with it, and it sounded balanced and quiet under the given circumstances. However, that is just my example.
I own a set of 184s. Now, I play mostly nylon-string guitar, so that's already more on the dark, mellow side, and the 184s work well for that, adding air and top-end detail to the strings, but others have said that the 184s can be too bright on top, depending on application.
Personally, if I were to mic a horn, even not having done it, I would first reach for a large-dia condenser or dynamic, just based on what I see and have read. That's just intuition on my part, not experience.
Someone else with "hands-on" in this can chime in, but I would imagine brass would get pretty 'cutting' with a mic such as the 184.
The prices you quote seem awfully high. Are you looking at the anniversary set of the 103? EBay has plenty of 103s from new on down.
Anyway, my two cents; I hope this helps you.
C.