Make sure to double up your support beams (vertical) and that will be all that matters, the horizontal ones will only serve to keep it together. By double up I mean wedge another section of 2x4 between the upper and lower horizontal cross beam, almost like creating a 4x4. I imagine you will need to level the support beams with shims anyway very likely, so a bend will not make a difference. Reference King Joey's DIY stand video if you don't know what I mean about doubling up the support beams.