I have been using inventorysource.com for the last eight months and have no complaints.
It is free to open up an account to take a look behind the scenes to see what they have to offer. One of the benefits is there automated service to feed products into a shopping cart website and all their suppliers carry these data feeds. The cost for the services is $25 per month and $15 for additional feeds thereafter at the time of this post.
I have a website that carries over 7500 products, could you imagine how long that would take me to update weekly for out of stock products and update price changes? This is where their service comes in as this is updated daily for me. A big time saver and worth the cost.
You can also push the products to eBay if you choose which is also a benefit for online sellers. Inventorysource.com also offers custom-built data feeds for Amazon, Google, ShopZilla and many others.
I've been doing a lot of research on drop shipping and there are some dropshippers that also offer data feed service. I believe that this is going to become a direction that these drop shipping directories should consider as technology moves forward.
I would hope Salehoo would consider implementing a category "Data Feed Suppliers" or consider a data feed service. This in my opinion would be a great service and a selling benefit to its members.
Hope this helps.