Many of the video converters on GOTD are similar because many use the same or similar code, e.g. they use ffmpeg because it could takes years & loads of money to come up with the same thing in-house. These Blu-Ray players take a similar approach, only here most rely on XBMC, a media center application. Like the converters there are [often slight] differences between brand X & brand Y, so use the player that works best for you.
Leawo's player added a service in the past, stored in a Appkeys folder in Common Files. I downloaded & installed a copy I downloaded from the link Leawo included in their registration e-mail -- when I installed it in a win7 64 VM it no longer added the Appkeys folder nor the service. This build also asks whether or not you want any file name extensions associated with the player, & lets you change that afterwards through its settings menu.
Now, retail Blu-Ray movie discs include always evolving DRM. It can be built into the Java code on the disc, &/or like DVDs they can make the disc slightly illegal re: the Blu-Ray video spec, &/or they can add Cinavia to the audio and so on, plus of course the basic Blu-Ray DRM. If you buy something like PowerDVD Ultra it decodes & works with that DRM the same way a stand alone player box would. It'll also handle the Java, meaning you'll get all the special features & Java-based menus. Check the XBMC site & you'll read that it does not do Java nor DRM.
I have no way of knowing how any of these XBMC-based players handle DRM, & since I have a few solely as backup players for Nero Plat & PowerDVD Ultra, I have no idea if Leawo's player works with more discs than DVDFab's for example. And even if I used one of them full time, there's no way to say the discs I watch are the same ones you do. Maybe it makes sense to have a few handy in case the disc you want to watch won't play in one or 2?
Whenever there's a Blu-Ray player on GOTD, seems there are comments on the order of "I just use VLC", or MPC or whatever... A Blu-Ray video disc may have hundreds of playlists, & the main movie on the disc may be in one file [the largest], or it may be split up into a few, or a dozen or more individual files. That means that assuming you use something like DVDFab's Passkey or AnyDVD HD to handle DRM, dragging & dropping a single video file onto the player's window is only workable *sometimes*. You really do need a player that understands Blu-Ray video discs if you want to watch them on your PC/laptop.