I went to the Magix site, and I could not read the system requirements, but it looks like PC only. So unless you have a Mac (or want to purchase one) I would think Magix or Vegas would be the way to go.
Please also be advised that while Final Cut and Macs are top drawer, they are also very spendy.
From the sound of it, I would advise you to upgrade your Magix; but also consider Sony Vegas Studio (or even Pro), because it will give you more room to grow.
