Back on the matter of VIC-20 games, should Cannonball Blitz really be a 7? It definitely isn't as rare as other Sierra games that are 7s like Lunar Leeper or Threshold. In fact, I don't think any of those are as rare as Creepy Corridors which is also a 7 (though I could be biased - that's the only Sierra VIC-20 cart I don't own ).