Best performing non offset Small block Mopar heads

I'm pretty sure Brett Miller was the man behind the first run of these that failed 3-4 years ago.

how did they fail? Were there multiple motors put together that were underachievers? i remember the thread here and the motor made decent power up top and was a little light on torque but it could’ve been the intake and borderline low compression if i remember correctly. So the heads weren’t a magic bullet so to speak. So were there other engines too??