The Good: Harp SciFi does a great job of allowing detailed character development, cool combat system and nice set of skill sets. I like a system that is not overly complex, but does not feel too fluffy in the rules. Harp does well at balance in this reguard.
The Bad: SciFi RPGs are a tough nut to crack since there is sooo much potential variation in technology and it makes "keeping it real" difficult. This is not a hard sci fi game - which is unfortunate as the system allows for more realism in the mechanics, it would be nice if they did more to "Harden" the scifi premises of the game. Also, it would be nice to have some more on spaceship combat/design - probably a future suppliment.
The Ugly: As mentioned by others, the setting. The aliens just don't do it for me and the background sounds like it was cut and pasted from many scifi rpgs of the past.
Summary - great game mechanics, could use some more variation in characters based on future potential of humans, genetics, and artificial systems. Buy the game - sure its a good system, but throw out the awful background setting.