Yes, you can disregard WEI and other synthetic benchmark results. What does your real-world performance tell you? Does it feel the same? If it feels like it's performing slower then create the RAID-0 array.
That being said, since your SSDs are only 80GB each, I personally would create a RAID-0 array.
I agree alteast after creating the raid youll have around 140gb as one "drive"
also make sure to disable your paging file(if you have enough memory, 8gb is more than enough) since on ssds it will decrease the lifespan of them