I have experience with the first two, and the third is just a large Virga (discontinued)
the contrail has huge panels that will sag a LOT in rain or humidity (such is the case for all things silnylon)
the rainbow and double rainbow are nice enough, but ive heard several complaints of inability to thread the long pole thru the center pole-sleeve.
If considering the Contrail, you may also want to look at the Stevenson's Warmlite and the Six Moon Designs 1)gatewood cape or 2)Lunar Solo
if you like the Rainbow/DR, you must check out the SMD Lunar Duo and/or the Refuge.
its been a long time since i fussed over tents. if you do solo trips, dont discount the amazing versatility of a hammock system. trust me, there are at least a dozen hikers i personally know and hike with that have converted to hammocks permanently
I have a Grand Trunk Nano 7 that ive converted the suspension to a Whoopie Sling for a total weight of 7.7 ounces. And of course, i use a te-wa underquilt
that is only 13 ounces. A 11 oz MacCat standard tarp in Spinnaker rounds out the package. see my article about hammock camping in the navigation bar, articles, hammocks as camping shelters.
or you could always get the 18oz tarptent sublite in tyvek.