User-friendly score software for Apple iMac?

Hi folks, I could really use your help with a recommendation for a Christmas gift! My brother plays the trumpet and euphonium for his church group and occasionally has to write music parts for himself or the other members. For Christmas he's asked me for some software for his Apple, which he can use to create and print musical scores.

It has to have the ability to transpose easily, and some flexible print options like bass clef, treble clef, or both. Most importantly it has to be very user-friendly (he's not a computer whiz) and it has to work on the Apple platform.

I've seen some references on this board to Cubase and Sonar. I've never actually used either, but a quick search suggests that the full versions of these are pretty heavy-duty for what he wants to do. Also, I think I downloaded a free version of Midi Illustrator (or something like that) a long time ago but never really used it.

I've never owned an Apple computer and don't have one now, so I can't really try any kind of demo version. Please share your recommendations!!
Thanks,
Ted

Not many people use this - but I do - I think it all started in my bad old PC days, and eventually migrated to Apple. Sonic Scores Overture. I find it quite comprehensive and user friendly and we can always use more users! It is up to version 5 now but I use version 4. I don't think 4 is available. Lots of templates, It has a dedicated lyrics box - where you can paste in the lyrics, so you don't have to type in lyrics