Has anyone checked into selling through Artist Rising, Photographers Direct or Fine Art America?

I'm new at this, have read some complaints about microstock (low pay out) and found these three web sites that sell at what seems to be a decent %.

I've sold some through local shops mainly 6 x 9 matted prints and postcards but also various sizes up to a 2' x 3' photo and would like to get some web exposure.

If there has already been a discussion on this just point me in the right direction.

thank you