After struggling with GoPro Studio's constant glitches and quirkiness, I finally got fed-up enough to search for an editor that fits my needs. For me that was something simple, reliable and actually usable. I didn't need a lot of features yet, just a means of basic editing without freezing-up. Very reliable! Two things I noticed that were minor issues for me: 1. - audio/video syncing during editing/preview was an issue that was solved by rendering often, 2. - I'd like the fade transition to be more smooth and adjustable but maybe I have to look into this a bit more. Overall a pleasure to use. I actually look forward to using it compared to the dread I felt using GoPro Studio, which isn't even available to download any more. Another appropriate review I read of GoPro Studio was that it was free, powerful and dysfunctional.
Video editing is one of the most computing-intensive activities around, so you'll want the best laptop or desktop you can afford if you're serious about cutting your own movies. Most applications help speed up the editing process by creating a proxy file of lower resolution, so that normal editing and previewing aren't slowed down by the huge full-resolution files.