If the be quiet follows the reviews of similar models (can't find a review of that one, specifically), then it'll have lower quality components than the tier A-B models, which might impact the PSU's lifespan (especially @ high temperatures) and it is probably based on an older design that is less suitable for modern systems, but since it claims to have DC-DC, it suggests the design is relatively modern. It also has 2x PCI-E 6/8 pin and 1x EPS 12v, so the connectors aren't ancient either.
I suspect these are just designed/intended for custom builds to be no-fuss PSUs that meet their warranties and maintain a competitive price for the more marketable parts of their build. So, as pastymuncher said, it is likely to be better than most of the cheap junk out there, but would I use one in my own PCs? No.