You seem to have informed yourself quite well about your options - great!
The gloss on the Das attracts fingerprints and also gets dirty fairly easy. Quality-wise, they switched manufacturers and it used to be better, so it depends on what version you get.
Filco is a good option that is often recommended, always a good choice. You can get replacement blank keycaps fairly cheap if it bothers you.
With WASD, I really think after taxes etc. the higher price compared to the Filco isn't worth it.