I bought Rockford BP Shiraz regularly from 1988 vintage ($16.50) to 2005 ($50) and then again my last buy was the 2010 vintage @ $58. I sold at auction most of what I had when I stopped buying. The last one I tried at the winery was the 2016 @ $72 and I thought is was maybe a fair $50 wine compared to the other wines we tasted on that winery crawl.
On the Barossa part of that trip I bough Langmeil Orphan Bank Shiraz (at mates rates, but full price similar to BP), and wines from Cirillo, Rolf Binder and Izway. Other Barossa wines I've bought recently instead of BP include Tim Smith Shiraz and Reserve Shiraz, Spinifex Indigene, Kalleske, Teusner Big Jim and a few others.
Rockford is a good marketing exercise, at vintage time they have small trucks arriving at CD and people hand shoveling the grapes into the small old-fashioned winery next to the CD. People never see the real winery over the hill. At the rate they process the grapes through the little show setup it would take about 3 years to process each vintage.