There are a number of things that are great about the 817nd unit.
First,.. I have one.
Operation Modes with the 817nd I have completed:
UHF/VHF Voice
HF Voice
HF PSK31
While 'barefoot' (no external amplifier) the radio only musters about 5watts on all bands, it does quite well. I have made a number of contacts on just 5w using UHF/VHF and on HF 20m. While I don't have my log book with me currently, I believe the longest contact was about 900 miles.
Antenna does play a key role in the reception and transmit range. My complete setup fits into a regular Dell laptop bag, with the exception of a 33' fiberglass kite pole.
I am quite happy with it and it's big brother the FT-857.