I've recently completed by first run of Dragon Age: Origins and I'm currently playing through Dragon Age 2. I can't find any faults with either of them so far and I'm enjoying them immensely.
That's cool but I have to say that in my opinion Origins was much better than 2, since 2 was pretty much rushed. You should try awakening which was a DLC for origins with a new storyline (and character if you want)