Answer: As with any tomatoes but perhaps even more so, the results with the heirlooms will vary from year to year and garden to garden. They will even vary within variety because they are just not as predictable as the modern hybrids.
Generally the Brandywines are all similar in overall productivity and disease resistance, but the productivity tends to vary as widely as with all the heirlooms. By the same token, every tomato fan has their personal favorite variety based on taste. Many claim the red Brandywine tastes the best of all, but in my experience they all taste great!
Brandywine often runs over a pound, Mortgage Lifter averages about twice that. Unfortunately I can't tell you which one will be more productive in your garden. You might wish to try several varieties and trial them under your own conditions to see which one more consistently does best for you over time. Good luck with your heirlooms!
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