RiME LITE Softboxes and
if they are available to you - get them. They are absolutely first class, with a fabric that even trumps what Chimera uses. The rods are made from strong Duraluminium.
Here's a link showing the design:
And the catalogue: www.hdace.com/catalog/2012_07_20_Catalogue.pdf
On a side note: using the D1 in softboxes requires to replace the flat glass by the dome (in order to spread the light 180°):