Let's see a picture of the current bike and of what you want to trade it for. I'm personally not a harley hater but do think some are kind of ugly/stereotypical. I don't own a BMW but think the uniqueness of an opposed german twin may outweigh the fairly common v-twin. But then again I get the new toy itch pretty often myself...
I think I effectively added nothing to this thread
1972 Honda CB450 (Rebuilding), 1971 Ducati 450 R/T (in the queue), 1971 Honda SL100, 1965 Ducati 160, 1967 Honda CM91/CT90 hybrid, 1986 BMW K75