I've had some articles get picked up a fair amount of times by publishers, but it never seems to generate much traffic. Sometimes it doesn't generate any. I'm sure its good in some ways, just not sure what.
google search the name you got your artilces writen under you should see you articles on ezine and you will see your name and articles from other peoples websites that have republished your articles, but the big thing is to see if your bio box link is still clickable on the other webmaters websites, well thats what i check for.
I think there's some SEO benefit but very little traffic benefit in most cases. I post articles with the ISnare as well and I seem to get very little traffic from the sites that pick up my articles but I do get some nice backlinks.