Where can I find a list of factors that a plan sponsor should consider when choosing a TPA or recordkeeper? It seems a lot of plan sponsors think that only one factor, cost, is relevant.

How about (1) background info, (2) implementation capabilities, (3) systems, (4) ongoing admin capabilites, (5) participant services, (6) reporting capabilities, (7) compliance services, (8) quality issues, (9) investment options, (10), trustee services, (11) communication & education, (12) Internet capabilities....?

Check out this website - http://www.psca.org/issues.html. The Profit Sharing Council has a number of useful tools for reviewing and evaluating all aspects of your plan.