If you make a considerable amount of salsa I would suggest that you grow the excellent paste variety Polish Linguisa. I have grown it and the Opalka variety for years now and the are the biggest, sweetest, meatiest salsa making tomatoes I have found. Linguisa is the hardier of the two, but I haven't had disease problems with either plant. As far as the other heirlooms listed above, what they are suggesting are great tomatoes, but most are slicers and not ideal for making salsa. You want a paste tomato for good salsa.