Hey Don,
I've also been looking at these two for next year. Looks like I've developed a nematode infestation this past year, so I've been looking for resistant varieties.
It appears that only the Dixie Red is nematode resistant, and it is a determinate variety. I was excited about Big Daddy, but as it's not nematode resistant, I'll have to pass.
Here's what I found on both:
https://www.burpee.com/vegetables/to...rod002743.html
http://www.tomatogrowers.com/DIXIE-R...ductinfo/5695/
Hope this helps,
Jon