A pretty crap ally with a niche ability. Has the distinction of being one of only four cards that currently remove conditions, and if the quest doesn't have conditions, at least he's still a body. Put him in your deck for Conflict at the Carrock, but otherwise you'll probably want to leave him in the box. Why do you need a miner to pull someone out of a sack anyway??
For the record, the alternatives:
Elrond: Expensive, have to give up potential card draw for the condition removal, which hurts more in multiplayer. Good card no matter what quest you're playing.
Athelas: Requires a matching character and exhausts them. The non-condition healing effect can be ok in general games.
Power of Orthanc: Even more niche than the Miner. Better as a silver bullet if a particular quest is really condition-heavy. The Doomed 2 will ruin you in Carrock, though.