experience/advice using 1.25 hitch with adapter for bike rack

I drive a 2008 Prius and have a Saris Thelma bike rack with a 2 inch bar that I would like to use. I understand that my Prius can only have a 1.25 inch receiver hitch. What are your thoughts about having a Draw Tite 1.25 inch receiver hitch installed and using a hitch adapter to allow the use of my Saris rack? Will the extra length of the adapter be a problem? I will only be carrying 2 road bikes plus the Saris rack. Will the adapter be able to hold the weight?
Thanks for your help!
Lisa