What a great topic!  From the employee benefits consulting side (my
niche) I struggle with offering commission vs. fee for service.  Our
testing ground so far is in asking our clients and prospects what they
think.  So far, not a lot of opinion form average consumers who don't
evaluate the equation (commission or fee = advice, service, and product
provided) at all either way.  Bottom line, we see this as a way to
differentiate ourselves if we can have an open discussion with clients
on what works best for them and AND be able to offer both models. 
Commission or fee discloure is coming one way or another… I say be
open about it and be ahead of the curve in your market before it is
mandated.