I have been lurking in this place for a long time... and have been getting really interested in all this BP&W stuff, which I found by searching for travel and compact BC's. I am interested in light gear simply for travel purposes alone, and I am one who will compromise a bit on trim underwater if I need too (which I don't believe i do for reasons mentioned in previous posts) to shave 5 or more pounds.
All my travel is backpacking, where I often end up hiking between towns, camping on the beach or in jungle, and 5 or 6 punds is HUGE when your carrying everything on your back. Scuba gear is not the only thing I am carrying when I travel like this (which is usually for a month or longer), I have a tent, sleeping bag, stove & mess kit, water purifier, food & water, along with clothes books, and cameras. This is why I have always rented gear, rather than owning it, but I am getting anxious to have my own gear... but it must be light.
That is atleast one valid reason for light gear. Airplane luggage is another one.
-MG