Tom's Hardware Guide published a review on Das Keyboard Prime 13
A quote from the article:
We review the Das Keyboard Prime 13. Das Keyboard is one of the more mainstream names in the mechanical keyboard space that isn't primarily making "gaming" boards. The flagship Das Keyboard lineup has gone through several revisions over the years (currently the Das Keyboard 4) but has always stuck to a minimalist feature set with optional blank keycaps?they don't even have LEDs, let alone RGB LEDs. The Das Keyboard Prime 13 is an attractive alternative that includes LED backlighting at a lower price than the Das Keyboard 4.Das Keyboard Prime 13 Review @ Toms Hardware