I only use this kind of programs to link to 2nd or 3rd tier properties. Never directly to my main url! If you do that often your page will go down instead of up. Just last week google announced that they are filtering the quality of backlinks. Meaning that these kind of links will be recognized and won't count as a link to make your site go up.
The more work you put into it, the better the link will be. For example you can creat web 2.0 properties with uniek content and get a backlink to your url form there. I've got experiance with that and it really worked for my websites and it still does!
Be carefull with creating backlinks 'the easy way'.