I've bought a few pieces from ShopNBC/Evine over the years. The quality can be hit or miss. I find QVC's quality still typically better overall than Evine's. They don't vanity size nearly as much as QVC. I typically take a small and sometime an extra-small with QVC clothing. I am not a small and I laugh at the fact that I have tags that say "extra-small". I'm a true medium in the department stores and I'm a medium with what I've bought from Evine.
I usually gravitate toward Kate and Mallory and OSO Casuals for clothing. All tops and sweaters because they really don't carry petite pants. I like that they tend towards more different and funky fashions. Not anything I think I can get years and years of wear out, but for the price worth purchasing to expand the wardrobe for a couple/few seasons.