I have to chime in for Fab here. What he is telling you is correct. Caveat: I have not tried Parked.com. The majority of my domains are at Fab, with the balance at SedoPro. I have been with Fab for about a year and a half now.
When you have a domain that works at Fab, it works really well. They have beautiful graphics, and top links. I have gotten upwards of $10 per click; usually it's between $.25 and $2.50 per click.
And my domains are almost exclusively non-gambling. Like he said, they do well with basic 1-2 word domains. I have a few longer ones like MaunaLaniRealEstate.com which I know convert that I bring to them, but that is the exception.
Their support is great, they work with you, and I have every impression that they are honest payers.
But...like he said, there are domains that just don't work there at present. I have a number of foreign language ones that are making much more at SedoPro, because Sedo translates the domain when it is opened in different countries. So domains which were earning very little at Fab are earning $10+ a month at SedoPro.
Kind regards....