Criteria to look for when selecting Self Directed IRA custodian

[Udaya P.]

I am looking to move my old 401k funds to Self-directed IRA.

What are the criteria, I need to look for, when selecting the custodian for SDIRA ?

I looked at two of them Horizontrust.com and trustetc.com as examples. 

I am trying to understand the pros and cons of each of the custodians and how do I chose one over the other. 

I am looking expert opinion from the experts in this forum.

Thanks

--uday