They will bush if you keep them trimmed and they wouldn't need a support. We built and arbor for ours because they're HUGE...we kinda let them get away from us. They're as easy to grow as the wild ones...we just throw some compost on them once a year.
I love my thornless blackberry...the amount of berries you get (and the size of them) is staggering!
I wonder if it is the same hybrid (no idea what mine is) .... the only thing I find irritating about it is the little runners which have thorns...they remain berryless and I so hate weeding them out! Mine is really more a vine than a bush...I have it growing on a trellis!
Will you have some available in 4-6 weeks? I still have frost on the ground here in WA.
I would love some of those in my garden. I planted some several years ago and they vine very nicely, but the fruit is the size of a small button...... They are also very dangerous, they will grab you and tear your flesh if you get too close.