Just a quick note for the intertubes archives and for my fellow shroomers. My experience may support or contradict your own.
I have had about a 50% failure rate with Kroger brand 90 second brown rice. From the ingredients and the Nutrition Facts label, it seemed to be a perfect match to Uncle Bens. It was about 30¢-40¢ cheaper per bag I think?
Of the same inoculation batch (6 UB & 6 Kroger w/ 1-1.5cc LC) under the same conditions, 3 of the Kroger bags either suffered wet rot or contam. The surviving Kroger bags took about twice as long to fully spawn.
I suspect that there is more moisture in the Kroger bags, btw.
(I am anal about keeping things sterile and utilize a laminar flow hood these days.)
This is not a perfect sample size! However, with pure UB Tek, I am still sitting at a 100% success rate for approximately 20 bags total. (No contam, no rot) Your milage may vary, of course. Additionally, I have just completed my lab today, so UB Tek is going to be rare for me from here on out. Regardless, no more Kroger brand rice bags for my mushrooms.