First, Hella is a Eurpean brand that has been around for decades and has a reputaion as one of the top brands in quality lighting. It is one of a very few (with Bosch, Marchal, & Cibie) that I would personally trust.
As to the Hella Micro DE fog lamps in your link -- I installed those on a Miata which I have since sold. They are about as effective as a tiny lamp can be, and seem very well made. Being fogs, the light pattern is wide and short, with a sharp horizontal cutoff. Good for fog lights if that is what you are after; just be advised they are not driving lights (which, basically, throw light much farther down the road).