BK510,
GE Bank pulled TransUnion for my Walmart card. At the time they pulled it, my TU FICO was 646. From what I have read, they normally pull TransUnion and they may use Experian on the West Coast.
Regarding the secured loans, I have also used secured loans to add a new line to my credit report. I had both of them at 6 months terms at different credit unions.
I will update my journey so far this weekend and will PM you a copy!