I think a major reason that autos won't do well outdoors is mostly because of how quickly they finish.
Autoflowering plants are pretty much done in 9-10 weeks; basically they skip the vegging stage. So basically, you're racing against time....how quickly can you get this plant to grow from seed in 9-10 weeks???
A lot of the sweet pics you see on this site of autos are growers who give their plants 20+ hours of light a day. With all that light, you can see how the plant can reach its full potential in about 2 months.
BUT, if you're growing outdoors exclusively, you NEED to have a good amount of direct sunlight, or the autoflowering plant won't get large enough to produce a sizable amount of stash..