what do you guys thing about this as long as the runs are straight.

it would probably need more triangulation than round tube

i would call your local offroad shop, or blue torch fab or someone that has experience with alot of cages.

what do you guys thing about this as long as the runs are straight.
thats a great question i was going to mix round an square in my build also. hope you get some good answers

Not too much is wrong with it, search. Main downfall is that is is heavier per foot. Otherwise, its just ugly, which isnt the point. So if weight isnt an issue, a well designed cage with square TUBE is fine.