Started smoking mexweed in 1973, and it was way better than any brickweed I've seen for the last several years. Never bought any since I've been growing since 79. Anyway back then it was generally good, sometimes great, $25-40/lid or ounce. Lesser quality bags were loaded with stem and seed, but still ok if you cleaned it up.
The brickweed I've seen recently is real shit, compressed hard as a brick (no pun intended), compressed so hard all the seeds are smashed flat and broken up to where they are impossible to remove. Mex smokers today are missing a major part of the mexweed smoking experience: having a big old seed explode and blow the coal off a joint, or pop out a bowl sending fire or a glowing seed down the front of someones (probably polyester) shirt. It was easy to identify stoners back in the day, we all had little holes burned through the front of our shirts we displayed like badges of honor, and there were clusters holes in car seats where burning seeds fell out and rolled between your legs.
A guy gave me a chunk (not a nug, a rock hard fragment) for me to grind and I could barely get it ground. I read somewhere they compact it with trash compactors and custom hydraulic compactors. Not sure how they could keep it from molding other than drying it to superdry before compressing.