Agreed... not sure how OP is looking to make up a $1500 gap with $500. If I could get returns on cash like that, I'd be retired already.
This brings back fond memories of MQM though... when we'd start seeing the rush of mileage runs towards the end of the year to rack up the MQMs for cheap. I miss some of those southeast Asia or Oceania weekend trips when DL flew to those regions, to get to explore someplace new and rack up MQMs at the same time.