What options are available to _losslessly_ trim mp4/m4v video in macOS?

I have some DRM-free m4v video that I would like to edit by trimming here and there. * QuickTime X ($0) * *Pros:* free, built-in to OS X * *Cons:* selector to choose 'start' and 'end' times is not very easy to use to get precise in/out * iMovie ([Free](https://itunes.apple.com/us/app/imovie/id408981434?mt=12) if you have bought a recent Mac) * *Pros:* free * *Cons:* can't handle mp4/m4v directly, has to be re-encoded [I believe] * QuickTime 7 Pro ([$30](http://store.apple.com/us/product/D3380Z/A/quicktime-7-pro-for-mac-os-x)) * *Pros:* Can make very precise (to the frame) edits * *Cons:* saves only as .mov not .mp4/.m4v * [SimpleMovieX](http://simplemoviex.com) ([$40](http://simplemoviex.com/SimpleMovieX/redirectStore.html)) * *Pros:* claims to be able to do this (although I tried the demo and found the UI so terrible I can't even verify if it works, and if it does, if it does anything that QuickTime X cannot) * *Cons:* appears to be 'abandonware' as it hasn't even seen a minor update in well over a year, [MacUpdate reviews](https://www.macupdate.com/app/mac/16311/simplemoviex) are nearly entirely negative, going back to 2009, including slow- or no- responses from the developer. Are there other _good_ options out there\*? If so, what are they, and what are their pros/cons? \* I specified "good" because Google is useless for topic as the results are littered with sites offering “reviews” of software that *by some mere coïncidence * they also happen to sell. (Most of the sites and most of the software appear very similar as well.) There's clearly a lot of _crap_ out there