I haven’t been too impressed with Append. If someone inexperienced uses it, imo, it sounds the same as original Miku. Still, her voice does, in some cases, sound a little less robotic. She’s not as good as Gumi though… my main problem is it sounds too different from original Miku. Even Append Sweet sounds… like a older, depressed Miku. The cute, energetic feeling is lost. So I believe. Personally, while I may not be entirely fond of Miku, there are TONS of great songs with her originally so hopefully not everyone starts using the Append versions. Unless, you know, they have talent.