advice regarding magic submitter and senukex

Hi guys, I've been using magic submitted for a few weeks now and have several websites that I want to use it on. I have built up half a dozen profiles and created accounts on all of the websites,blogs and bookmark sites etc. What I want to know is each time I want to use it on a new site should I be creating new profiles everytime so new bookmark profiles or should I be using the already created profiles and website accounts and post new bookmarks to them as they should already be indexed by Google. The same question applies to senuke as I used that before but didn't get on with it as well as magic submitter. I'm just wondering if posting to an already established blog or bookmark is better then creating new ones everytime?