It does not compare, because they do not do the same thing. Handbrake is a video transcoder. LosslessCut cuts up videos specifically without transcoding.
So, not in reply to you, but the parent. It then seems entirely accurate to say they are not comparable.
Ffmpeg as workhorse is common. But what handbrake and losslesscut are in terms of (mostly) UI, they solve different problems, of which there isn't much to compare.
