Recs.
Updated
Although Blender is mainly a 3D modeller/animator/editor, it includes a fairly powerful sequencer editor.
SpecsUpdate
Pros
Pro Has a powerful rendering engine
Blender runs the Cycles path tracing engine under the hood. Cycles is a very powerful rendering engine capable of full path tracing (light fall off, caustics, volumetrics). It is mostly compatible with OpenCL and CUDA rendering, and is implementing mycropolygon displacement features. The upcoming release has a viewport engine called EEVEE whereby you can see and interact with your work in render mode in real time!
Pro Has good community support and many tutorials
I can always find answers to my questions just by asking google. The community is very active, and there are many tutorials for any job, from simply change speed, pan and zoom in your videos to color correction and compositing. With different workflows described, told by different people, in different ways, so you can pick ones that match your level of skills, and personal preferences.
Cons
Con Common video editing operations are complex
- Preview very slow (need to create a proxy 25% the scale and also resize the render output and even then it's often still slow)
- Doing a zoom (pan/scan) requires hacks https://blender.stackexchange.com/questions/42094
- Transitions are fully manual
- Playback speed adjustments are very manual especially if you want to keep them in sync with the audio.