I played
this engine game yesterday. The game itself was fun (164 points in 14 turns) but not that special (sort of mirror won by P1), and by now I've had my fair share of goons engines.
So it's not the engine itself that surprised me here, but the effectiveness of starting it up with Jack.
When I opened with Jack here it felt ok but not much more then that. I was even in doubt for a while. Looking back it seems like an uber-must-buy.
It seems like the combination of awkward destruction (Mint & Watchtower), relatively expensive engine components (3, 4, 5, 6) and the explosiveness of the final engine (Goons just does that) combine into making this the perfect Jack board.
On rare occasions I've seen Jack shine in other engines with Spice Merchant and/or Remodel, but all quite pale compared to this.
Maybe he is off-all-trades after all.