Why do we serve God?

Ok here's one: Do we serve and worhsip God because He is good, or because He is powerful? Which is it that makes Him worthy of service?

A while back i was watching Stargate SG-1, and they were working with this group of people on this planet and trying to convince them not to surrender to this other group of aliens who claimed to be gods. And at one point one of the stargate guys says that he doesn't doubt their power, just their worthiness as gods. So the question is, how do we pick a god to worship? Does power alone make the decision? If so, what if satan somehow managed to become more powerful than God - should all the Christians just switch sides?

But what if we discovered something about God that didn't seem right? What if He wasn't really completely honest, or less than perfectly just? what if He was less than God should be? would that then give us the right to stop serving Him? (Do we really have any "rights" in this context at all?) I know for some people, they refuse to serve God because they believe He is less than worthy of their worship. Should they give in anyway because of His power?

Of course, what we have to realize is that we really don't understand enough to judge God's worthiness. all we can compare him to are our ideas about justice and goodness. After all, isn't God the one who tells us what is good and right - rather than the other way around? But, on the other hand, would we encourage people to follow any spiritual power that could influence the world, regardless of its nature and character?

This is really a moot point because God is, in fact, both good and powerful. But for those who are still trying to choose which (if any) god they will serve, should we encourage them to pick based on power (which is posessed in small quantites by many evil people and spirits), or on worthiness, which we aren't fully capable of judging? Of course we could say both, but i do wonder if one is more important than the other.