I plan to use the strong and flexible plastic. I don't think my model fails any of the material guidelines listed for the plastic. I'm just wondering if there's a way to create my model with no supports for the top extrusion. Would it be better to have it printed with no hole and try to drill it once I receive it? I'd like to know as well for anything I design in the future.
If you are just worried about support for the loop - the printing process for the strong&flexible is different from the "FDM" method
used in home printers. The layers of un-fused powder within the hole act as the support material and are simply blown out afterwards.
(Watch the "how it works" video linked from the footer of the webpage, or one of the other shapeways videos on youtube)