Any of yall used one of these?

So how does a dyi guy do it themselves? Why does this machine not work and an exhaust pipe bending machine does? They seem to do the same thing . Maybe bending it a little and then moving the pipe a 1/4" or so and having a lot of patience would do it . I've always wanted to try it but couldn't get the nerve up to buy the machine .

I've had good results buying the pre-mandrel-bent exhaust pipe "kits", cutting them into pieces then welding them to make the bends I want. I also made duals for an M-body by cutting cardboard templates and taking them to my local muffler shop and having them bend the pipes, very cheap and quick but most shops use compression benders which reduces the diameter by 1/8-1/4"+ at the bend.

I prefer the cut-and-weld method since it makes the cleanest bends with the best flow and I'm not afraid of welding exhaust pipe, just takes a little practice with a MIG.