Stick with some disease resistant.... Liberty, Sundance, Enterprise, etc. I like Arkansas black, Querina, Freedom, Gold Rush, etc. I'd also look at some asian pears and some disease resistant pears. Maybe some pears like Kieffer as well. I could go on and on about apples & pears so just read Dbltree's apple & pear tree postings. Make sure the plant sites are kept weed free. Make sure you protect the trunks perfectly and do not allow deer to rub them or rabbits to girdle, it's huge. If you plant and have a drought, you better be willing to water them in critical times or they will die. If you need more on varieties, lemme know.