The HARP system is basically the offspring of the old Rolemaster system. It reminds me of MERP (or Middle Earth Role Playing), which was a simplified version of the Rolemaster rule set.
HARP sci-fi and HARP are very similar. If you did not like HARP, chances are you will not like HARP SF.
This book is not for everyone. The rules contained within are very crunchy - maybe not as crunchy as Rolemaster, but still. If you prefer rules light systems, steer clear.
The art contained within is decent and appropriate for the subject.
Overall, if you prefer realism over ease of play, this might be for you. There is a real lack of decent and innovative SF systems out there. This might be the one that does it for you.
[4 of 5 Stars!]