Lonnie - Right now those two tubes go forward to the tubes next to your legs. It adds another connection between the front and rear sections of the chassis. I'll snap some better shots later. Its essentially the same as the side of an original 7 frame.
I don't know if I'd go as far as calling it professional. Its still amateur work in a garage.
Homebrew - Out of all of my tools, it is one of my favorites. A few things really sold me on it:
1) Being hydraulic and with an air motor on the cylinder I can literally drag a recliner into the garage, sit back, and bend away without breaking a sweat - it sure beats manual benders.
2) Its portable and it bends vertically so it takes up very little floor space. If the garage ceiling isn't tall enough I can always drag it outside (never had to).
3) Since it swings vertically, I do not need horizontal clearance for the tube to swing while bending (huge plus when you are not working out of a warehouse).
4) You do not need inserts in your floor or a solid object to mount it to.
5) Mine was $550 ready to go (one die set included). Fair enough I saved a few bucks by using a 20% of coupon at HF and not doing the Type B model but you will be hard pressed to find a new or used hydraulic bender for anywhere near that price and have it be ready to bend.
With that said I can respect a comment Kurt made that you can get a cage bent for a few hundred dollars and not have to trip over the bender later. Really this is the only downside to this tool. As long as you have room to store it somewhere, I say go for it.
Regarding the sides being inside of the cage, I did this to keep the cage away from the passenger compartment but to still have something to mount the skins to. I was seriously contemplating leaving the tubes out and bending some sheet metal to look like there was a side but in the end decided to make it structural.