That was pretty awful. The game is basically a small set of tedious levels leading to boss fights, the problem being that you don't get any reward for actually playing though the levels, and running past everything trying to kill you seems to be a much better option; there is nothing at all stopping you from doing so. Also, in most cases, enemies (as far as I can tell) spawn endlessly, making sticking around to kill them all the more pointless. Due to this what you are left with is a series of boring boss fights where you spend your whole time blocking and dodging hits while your energy bar recharges.
The story is also a little strange. Don't get me wrong, it was fun to play the bad guy in such a black and white franchise, but you kind of turn good which is a shame. Also, strangely, if this were to be the accepted story between Star Wars Ep. 3 and 4 it would mean that Darth Vader is essentially responsible for founding the rebellion as a means to take down the emperor - maybe that is still the case, I am not sure, I haven't watched the new movies.
The game certainly isn't worth revisiting again, and I don't think I will bother play the second game in the series, or any other hack and slash in a hurry.