Hi Loscocco,
I have tried both in the past ( distant

), too be honest unless it is a real premium domain, one that you are realistically going to get $xx,xxx for ) I would not bother.
Most of the people going to these sites looking for a decent domain will be willing to spend the time to search for it, so are not really going to take much notice of 'Featured' domains.
On the other hand if your domain is going to be of a lower cost and you are willing to pay the fee then it will help as people looking for these type of domains take more notice of featured listings.
In my opinion for a domain in the mid $xxx I would go for Afternic, however getting on that list is very difficult as it is very limited and is only open when someone drops of the list.
Personally I still think the money is better invested in getting hosting, putting up a site and buy some advertising.
It is difficult to say with any accuracy without knowing the domain name you want to promote.
Also feqatured listings are quite good for decent quality domains that might not show up in the searches potential buyers will make.
All the best.
Richard