Nice one, Chris. I think that checks out with what I wrote earlier: that these cheapies are about two f-stops from the big boys in terms of noise performance (i.e., ISO X cheap ≈ ISO 4X expensive).
Re attached: ISO 6.4 & 25.6k, basic kit lens, zero skill, JPEG only, 8-bit levels and resize in GIMP, no processing hocus-pocus, wysiwyg; the Exif data is still there if you want to have a closer look at what you're getting. But if you're still worried about the noise for your ~$300 worth, I recommend getting some earplugs from your local chemist.