Well, I'll chime in. I use a bugaboo bivy and a tarp of some sort for exactly the situation you describe. The waterproof bivy allows me to take a paratarp and pitch it off the ground. It's a very lightweight and versatile system. If I think I'm going to be out for the night I take my bag, bivy, and pad and go. I had a tigoat and personally didn't like it because I felt sausaged in it with my bag and pad -- they may have changed it since then but that was my experience.
The only time I'd get the 3 wire is if you were going to bivy exclusively. The added bulk and weight isn't worth it otherwise. As I always say on this topic - It's always a compromise at some level, either weight or comfort. You just have to figure which is best for you. Oh, and with the eVent fabric I never get condensation in my bag. It breathes wonderfully.