It's in line with the FSP Aurum series of PSUs. Virtually identical. Before you say some of Be Quiet's units are FSP, they change nearly everything on the platform and are better built as a whole, especially when they focus on pure silence and quality of the product.
Edit -
Just an update on the list. The EVGA Supernova GS has been moved down a tier, as the platform is based on the Seasonic G series platform. It's in line with Antec's Truepower Classic and EDGE series, XFX's TS Gold and XTR units (XTR possibly being bumped up thanks to the new KM3 update on it) and Fractal Design's Edison units.
As for the Corsair RM 850w, there has been a recent review by
JonnyGuru on the 2015 update, using mainly Japanese capacitors and Polymer Apaq Capacitors. The fan controller has also been improved to be a bit more sensetive to temperature now. This unit has been bumped to Tier 2 as a result of the updated platform.
And just a question on those new Andyson units. Tier one or should they stay at Tier 2?