I read the stories on the 6mm BR website and believed that VihtaVuori N-133 was "the" most consistant powder. I had a can of IMR 8208 and tried it after a scope change on my 6mm PPC to "just get on paper". I ran a chronograph and was impressed with the extreme spread and SD. It was a HMMMM? moment.
After testing IMR 3031, H-335, R-15, 2000-MR, VV N-530 and N-540, N-133, H-4895, in the caliber, I ordered a .204 Ruger custom barrel thinking I would run N-540 with 40gr Sierras. By the time the barrel arrived, I was even more impressed with 8208. It is within 30 fps of N-540. Both powders are much faster than the rest of the pack. With HBN coated bullets I am sure my pressure is below what is listed in the Hodgdon website for maximum load of 28.2 gr yet the velocity is over 3900 fps. It takes more pressure to beat it with VV N-540 and it is harder to measure because of its coarse grain size.
I am building a .20 PPC now and plan to use 8208 early and often.