I've ordered from both of them several times since 2009, including chestnuts and hazelnuts from both. I've had pretty bad survival rates of stuff from Badgersett, and much better survival rates from Oikos. It's too early to tell which will yield more as production is only beginning, but the form of the plants have many differences already, with the Oikos ones mostly growing faster than anything from Badgersett. Oikos has quite a variety of strains itself.
I think the main reason why I've had such poor survival with anything from Badgersett is because their shipping times are wrong for the climate in southern Missouri. All the Badgersett plantings I've done were in 2010, 2011, and 2012, three years in a row with extremely hot, dry summers. Despite watering frequently, plantings of Badgersett tubelings that were sent in June had about 90% mortality within a couple of months. Badgersett reccommends planting them in early summer, but they are in a much cooler climate. If you're in a hot summer climate and want to order from Badgersett, I'd reccommend getting the bareroot tubelings shipped in spring. I planted some of them in April and still had about 50% mortality that summer, better than the later plantings but still bad. Almost all that survived the first year are still alive, but still seem to grow more slowly than the Oikos selections.
Plantings from Oikos during the same years with similar soil, watering etc. had less than 25% mortality. I think it's partly because they had better
root systems on arrival, but also because they ship at more reasonable times for this climate. November is the best time for planting here, but early/mid March is also pretty good, and Oikos will usually ship them when I want them. Badgersett won't even ship their bareroot tubelings until well into April when in many years, the
trees in this area are pretty much leafed out.
If only Hidden Springs Nursery had nut trees. I've ordered many fruit trees from them and have had almost zero mortality, with their trees almost universally getting off to a great start. I've never found another nursery like them, but unfortunately their selection isn't that huge and they don't do nuts, only fruit.