With the lower grades of the different brands one can expect about 1/4 gram of clean ass red per box, sometimes a little more with the obiviously superior types within the same brands. Yeah only about a half ounce a case, from the shitty kinds.
Swim too has heard reports of a gram per box, but doubts the cleanliness of the RP. Swim would rather have 1/4 gram clean RP than a gram of dirty RP that needs to bee cleaned. Dirty red will and can foil a reaction, take no chances with MBRP.