The reviews here seem to be mostly "plan to, want to, expect to".
I'll make this short and sweet...I put in two bales this year as a trial and the results were not good...there were incredibly good!!!
I put in four tomatoes, three peppers, a zucchini, and a lemon cucumber on two bales, consciously trying to stress the concept to see what it would deliver.
I will never garden any other way! The plants all grew rapidly and have been exuberantly productive. In addition, for the first time in 25 years living in this location (San Francisco Peninsula), I have not had to fight the slugs and snails! One tried to climb the bale but gave up. What a relief to be freed of that struggle.
We're waiting for the huge crop of tomatoes to ripen while we harvest zucchini, cucumbers, and peppers.