Hey guys, i've been guest posting heavily for one of my projects the past 3 weeks. Most of them are not exactly high authority sites (so da20-40 and tf 20-40). Should I build any further links to these posts or leave them as they are? And what would you do? some random pbn spam (like this, or this), just a couple of web 2.0 or even a quality guest post service (tho they are kinda pricey)? Any recommendations? Oh..and would u mix in the keyword or leave it at pure brand and naked links?