
I've used worm count in the past, maybe once or twice. It successfully picked up tapeworm in my GR and then I wormed all of the dogs. It is reliable and it isn't.... It's a snapshot of a time. So the results will either be eggs seen or eggs not seen. That doesn't mean there are no eggs, but that none were seen in that sample. But I have heard of several positives- there seemed to be a lot of lungworm positives a while back. So it does work. But to more of another tool than a fail safe method.
What I tend to do is worm count according to my dogs' behaviour and condition. If I suspect a problem, I test.
http://www.wormcount.com are brilliant. I sent my dogs' samples one day and had the results by email the next, including helpful advice when one dog tested positive.