I used the Reverse Beacon Network
as a skimmer spotting feed during contests. I use VE7CC's AR software to set up filters, so I only see spots from skimmers in my region, otherwise you drown in spots you are likely to never hear.
I like human-powered spotting for general DXing, as skimmers don't give you "UP" or "EU only" type comments. Actually, I'm doing more spotting-free DXing, as it is much more fun to find them before they are spotted. But for that first glance at the bands when you sit down at the key, nice to see what is out there with spotting.
73 John K3TN