You might consider selling the 817 and getting a KX3 for your portable work. 10 watts is 3 dB better than 5. They have a 2 meter add on for it now, too.
The 991 looks OK to me - if someone gave me one I wouldn't throw it out. It might eventually become a replacement for my ancient IC-746. I don't think it would
be a very good portable, though - I bet it sucks battery power at a serious clip. You might want to check the specs. I looked at their ads and they don't list receive current drain, and their website rejected my attempts to download a brochure.