Understanding LinkPop?

[Mr.Domains]

I am using the StartName LinkPop tool:
http://www.startname.com/linkpop/index.php

I have found a couple expiring domains with Google linkpop:

Domain Google w/ext Google w/o ext Total
gxn*****.com 2,350 2,340 4,690
51******.net 179 465 644

The thing is, if I search for these domains in Google, either using "quotes" or "site:" or "link:" I get no results!

So what does this mean?

Are the domains worth registering or not?

Should I be using a better LinkPop tool?

 

[DNjet]

go to uptimebot.com and you will see if it has linkpop ,and if any indexed pages , and also if it was mirrored.