This is a combo Blu-ray Copier/ripper, though in a roundabout way -- it copies the contents into another type of file container, e.g. MKV instead of the Blu-ray native .m2ts. You *should* be able to swap the contents of that container file into another type of container, or split it into the individual components, e.g. audio & video, as necessary to work with your preferred hardware [e.g. Blu-ray player] or software. videohelp[.]com has info & tools.
I would suggest buying the software, because Blu-ray DRM is constantly evolving, & that requires software updates to keep up. That said, bypassing the DRM on a Blu-ray disc might be considered risky by a software developer, since the company behind one of the DRM methods successfully took DVDFab's parent company to court. In that case no one appeared for the defense, so a default judgment was awarded -- DVDFab could no longer do biz in the US, lost its dot com address etc. Given the current political climate, ThunderSoft risks losing its access to the US, & potentially EU market. If they later decide it's too risky, they could stop selling their Blu-ray ripper, & with no updates it would become useless. At today's $10 price that's not a huge deal, but at $40 it might be a good reason to pay more for DVDFab Passkey, since they've already weathered the penalties & are still going strong.
The app itself adds the program's folder, plus a folder in Users\ [UserName]\ AppData\ Roaming. The registry gets 2 keys, one for the app & one for uninstall. It uses ffmpeg, like most every other ripper, with the main weakness that it can't do decent mpg2. [Mpg2 is actually a decent Blu-ray format, and while not as efficient as the H.264 commonly used, it's Much easier/faster to encode -- several video editing apps use it for Blu-ray encoding.]
The hard part is handling the extensive & always evolving Blu-ray DRM -- possibly [probably?] the reason WR had poor luck with the Chaos Walking disc [posted in the comments]. Blu-ray video itself is almost always encoded as AVC/H.264 -- the spec includes mpg2 & VC1, but you'll never see a retail disc using those -- and pretty much Any device can play its H.264 video. On a Blu-ray disc the video's in a .m2ts container. The only reason to put that video in another type of container is if your preferred software doesn't recognize .m2ts -- VLC does, and it's available for Android, including Kindle HD tablets. You can get MakeMKV for free, and it copies the content stored in .m2ts files into .MKV containers -- ThunderSoft Blu-ray Ripper can do the same, or you can use another type of container, mp4. Same as with DVDs, the time it takes to copy a Blu-ray disc is determined by the file transfer speed, so if/when you're doing a lossless copy, No software going to be faster or slower at the task.
Blu-ray discs can hold up to 50GB -- often the main movie is around 30GB, so you save quite a bit of disc space if like WR you copy only the main movie. Copying just the main movie you'll also likely get a single video file -- the Blu-ray spec allows splitting a single video over several .m2ts files, and not every player will use the playlist that ties those files together, and in order. Note that as part of a Blu-ray's DRM, it's common to have very many playlists, many [most?] of them fake, along with added .m2ts files, so the only way to determine if a copy or rip was successful is to watch the original, then compare it to your results, e.g. scenes can be swapped or missing.
Blu-rays also like to include HD audio, and if you keep just the *ordinary* 5.1 that also saves some space. That's something that I think is easier to do using Tsmuxer with a copy of the full disc on your hard drive -- it'll copy just the main movie, as a single .m2ts file, strip out the HD from the audio, and put everything in a Blu-ray folder, but you will need to know the real playlist to use.
Subtitles are trickier, since they're stored in a separate stream and made of graphics rather than text. The .m2ts container can store audio, video & subs -- so can MKV, BUT, not every player that can handle MKV will display those subs. A *maybe* better alternative takes a little more work -- use something like the free SubtitleEdit to OCR the subs into an .srt file. Give that .srt file the same name as the video, and very many players [more than will play .m2ts] will let you turn sub display on/off, and at the appropriate size for your display.
You can make the video files smaller by re-encoding them -- you can reduce the frame size, including making it anamorphic, and you can increase the amount of video compression [reduce the bit rate], but you'll Always lose some quality. H.264 video is harder to edit &/or use as a source for re-encoding -- it's Very easy to lose audio sync, so be sure to check your results. The encoding part [adding video compression] can be very CPU intensive, e.g. using H.264 or H.265, taking quite a bit of time -- the better the quality, the longer it takes, and spending 24 hours at the task is not unknown. On the flip side, apps that encode more quickly than average often use encoding settings that reduce quality. Like most rippers, ThunderSoft Blu-ray Ripper compromises on the encoder settings used in the included profiles. You don't have to use something different if you don't want to, but know that you can get better quality if you re-encode a lossless copy using an app that gives you more control over those settings, or even the x264 encoder bundled in ffmpeg by itself. You could also save the original DTS or AC3 audio, which may be more compatible than the AAC ThunderSoft Blu-ray Ripper usually uses.
For someone like WR that wants to manage their Blu-ray collection on regular hard disk storage, I suggest they consider using the Blu-ray format on their hard disks as well -- it simply amounts to a special file & folder structure, though you'll want to stick with the original video, or use Blu-ray spec H.264 or mpg2 encoding. Players that don't understand Blu-ray can still play the single .m2ts file with the audio, video, & subs, while you can do stuff like copy the movie in Blu-ray format to a USB stick, & it'll play in a Blu-ray player if it has a USB port.