I know how you feel StigVidar.
Since I was facing the same dilemma before.
My FA*80-200 is heavy but it produces such beautiful photos.
Finally I resorted with DA*50-135 for my mid tele & weather sealed zoom for my most portraits but I'm still keeping my FA*80-200.
I don't know why but it's just too hard to part with this lens.
Haven't seen any 80-200 zoom range that can beat this lens. Not even the DA*50-135, it might have similar sharpness but not with the colour. Especially at 200mm/2.8...oh how much I love the bokeh smoothness.
I was dreaming of full frame camera and when I look into Canon 5D & 70-200mm L IS, the Canon 70-200 has the similar weight. So, it comforts me knowing that to achieve that speed & IQ for a lens, that weight is justifiable
Who knows Pentax will releas Full Frame next year ;P (...I know, it's just a dream...for now)