I have not used Xrumer but from my understanding its a spam bot that will get link posted of lots of places. My plan it to create around 50 domains with cheap content on the theme of my main site. Then use Xrumer to get links for these 50 sites. Then I will link these 50 sites randomly to each other aswell as to my main site. I think this will work really well but if the links that xrumer generates do not last long it wont be great. Do many of the links generated by xrumer last more than 6 months? I'm thinking of googles link aging filter here.