The Das acquired a bad name for itself because of a version released two years ago which they sold until quite recently which had some terrible electronics issues. It has since gone through two different revisions and the electronics problems appear to have been fixed. Another common concern was that the keycaps on the lettered version were prone to wear. They have since been replaced with keycaps that are probably more durable than the ones used on the Filco. Either way, given that you're using the blank version, this isn't really an issue.
What it comes down to here is taste. The Das has some features that the Filco lacks. They have a media key functionality built in which some like and some dislike. They also an integrated USB hub, however, the hub requires a separate USB cable which somewhat mitigates it's usefulness. Aside from that, it's an issue of aesthetics - you might like the shiny look of the Das, others will prefer the minimalist matte look of the Filco.
Remember at the end of the day that both of these keyboards come out of the same factory, and now that Das fixed the electronics issues that they have, they are quite similar.
