Hello redneckreject! I like your question and I will do my best to answer it.
When it comes to cost pastured turkeys are lower cost by 40-50%. They simply forage most of the day finding bugs and eating grasses. We use a small amount of food to get them into their pen at night.

The Cornish cross will be 8-9 lbs at 9-10 weeks and a young pastured turkey will weigh more but yield the same meat because of the larger frame at 6 months.

The Cornish crosses will be a more tender meat compared to the turkeys that walk around hunting for the majority of their food. There are many good slow cooking recipes for turkey and chicken making it difficult to tell the difference. But if you want to grill a chicken or turkey you will find the turkey on the tough side.

The turkey compliments a homestead by eating bugs that eat grasses for your grazing animals but a Cornish cross is a high consumer of typically purchased food. The Crosses do yield some high litter amount which can build up poor soils.

In summary if I am looking only at it from meat I would say the Cornish cross would win since it is what you currently buy in the store. The big difference will be how you raise them...pastured and high quality food.