Big vote for vertical. Our vertical benders have an option for carts on casters, so if you ever have more than 8 feet to swing up after a bend, you can just roll it outside and bend and bring it back in.
I have never once had to roll one outside for a bend.
We have done repeatability studies and ran the numbers on the results. We can consistently get standard deviations of 0.11 degrees on single bends. I have never bothered to run statistics on bend plane and spacing, but we made 13 bends in one part and laid it on smooth concrete and had a little more than nickel under the highest part. It was for a rock crawler build, so that was better than it needed to be. We used nothing but our eyes to line it all up (our machine is easy for that, there is a machined edge always tangent to the bent leg of the tube when it is sraight
). Probably could have done better with a level and a fixture.
Let us know if the other model 32 works better for you!