Kelly, lots of good information!
I was reminded about how easy it is for rootstock to spread disease if it is contaminated ... a problem familiar to rose gardeners in the US. Hoping that there is rootstock that can be grown from seed to avoid this problem. Or that Territorial Seed is really good at avoiding the problem.
My own plants are arriving first week in May, hoping to avoid late frosts. I'll try planting one in a pot and compare it to a Roma tomato grown from seed and grown on in an identical pot. And maybe I'll try one grafted tomato in the native soil here, along with the dozen or so Romas growing from seed right now.
I am perhaps the world's worst tomato gardener. I kept a dozen plants alive through summer last year. Altogether they bore two tomatoes of which both were partially eaten by the local wildlife before they got ripe. So I got no tomatoes at all from a dozen plants.
Hoping for better results this year. Thanks for the pasting the entries above!