what to do when you have many domain options available?

Lets say my keyword is "x", and i have all these domains options to pick from, what would you choose? I can't decide which to pick and I also am thinking if i should setup other sites with these options to create backlink, PBN sites. would that be optimal?


xtutorials.org
breakoutx.com
xdiaries.com
xfilter.com
xessentials.com
citizenx.com
xpit.com
xstarter.com
xphoenix.com
indigox.com
xcache.com
weekendx.com
processx.com
primaryx.com
progressivex.com
xsyndicate.com
primalx.com
xdriven.com
xjunky.com
granitex.com
xfaqs.com
xboulevard.com
xblvd.com
rocksolidx.com