Zenbook Prime UX31A SSD Replacement

I'm planning to buy an ultrabook and I'm leaning to the UX31A. My only concern is the SSD. We know that SSDs have a limited number of P/E cycles. I stream many videos especially in YouTube and most are HD videos. Those videos, if I'm not mistaken, is downloaded by the browser and stored temporarily on the HDD. This means that the SSD on the Zenbook I would be buying will wear out faster.

So my question is how can I replace the SSD on the ultrabook that I would be buying? Also, in general, do SSDs on ultrabooks replaceable?