I have Machete Pro since years - I think I was one of the first paying users. It was only $19.95 at the time,
It is an excellent tool for pasting clips together - the only editor I know that is super fast and does it in a completely lossless fashion. But the pieces have to be identical in their specs - framerates, sound, frame size, etc, etc. Since Machete does not reformat the video, they cannot handle any deviations in any parameter.