You are right, of course. It is just that the F5 and the SB-28 have grown to love and need one another. I can't break them apart after all this time together, just for the new girl in town. This combo works. I know what to expect EVERY time I use it. If it ain't broke, don't fix it, etc.
The first time I go shoot a wedding with the F5 and SB-80DX, I'll probably find that it underexposes every twelfth shot, when the moon is full, and the bride is blushing. With the F5 and SB-28, I KNOW that won't happen. Give me a few years with this newfangled SB-80Dx and I'll feel the same way!