Although I have used MuseScore for free for years, I haven't bought into any of their promotions. If you haven't used MuseScore yet, it might be a good idea just to download their free site and get used to using it. Then, if their offer appears again (it will!), you can decide whether it's worth the enhancements. I use it to transcribe, copy, and put down all my compositions, going back as many as ten years—solo lines, instrumental solos and duets, choral music, piano accompaniments. It's powerful, and I'd be hard put for my skills to exceed its many functions.
Tom