The trick to the halloween shows (and that dsotm show) is that they were 1 offs, practiced in secret. They were events. Lots of fun to experience. Not groundbreaking. But quadrophenia was good, as was VU loaded.
I really enjoyed the cover summer of 98, when they did a ton of different covers. Their version of sabotage was great fun.
As for mule's covers, back in the day, they were awesome. Now that mule's a 4 piece, I dunno, I haven't paid attention. But warren haynes is the most talented guitar player alive, imho.