Masterpiece is closer to the original Myst experience with the prerendered visuals and slideshow presentation but with enhanced resolution and colors compared to Myst's original release.

realMyst has a more modern look but one that's looking rather dated these days. Movement in realMyst is arguably more "painful" than the point and click slideshow. realMyst's movement controls are quite archaic and unintuitive.

The differences between versions are otherwise identical, except realMyst has some optional end game content.

For a more classic experience similar to Myst's original release, I recommend Masterpiece

In my opinion, only realMyst Masterpiece graphics look cheap compared to all other versions, but that's because I think the texture work makes the game look like a Fisherprice play set. The polys and textures as well as the lighting of rM:M might be better than that of the original realMyst, but I personally dislike the texture pallet.

Thank you, I think i'll try Myst ME then, I'm used playing old point and click games at the moment!

Play both, but do Myst ME first. The game goes through some changes in each version, so you're not exactly getting the same experience with each version. See my post here for example:
https://www.gog.com/forum/general/real_myst_is_leaving_gogcom_on_the_18th_70_off_discount_now_active/post72

I prefer the feel o the ages from Myst ME myself, but I do enjoy seeing how they look in Realmyst and Realmyst ME

If I play the game again I'll try a different version certainly!

I played Monkey Island 1&2 recently, for the first time, and I enjoyed switching all the time from another version to another (you just have to press a key), I liked to see the differences and both of them have their charms.

So with the 25th anniversary release of the Myst titles on GOG, I've noticed that the reviews for Masterpiece Edition say it doesn't work on Win 7 64bit (which is what I use). But, they were old reviews. Just wondering if the these older games that have already existed on GOG have been updated to work on modern machines too?

Yes, the new releases run wonderfully on Win10x64 (what I use, RS5, build 17704 atm--I beta test Win10x64 through the Insider's program), and according to GOG on Winx64 7/8.1, too--but nothing else apparently (?).

In fact, prior to the release of the 25th Anniversary editions of Myst, I was able to run them all on Win10x64--even the older commercial releases of Win10x64--except for Myst III & IV--which I could never get to run on Win10, any version, no matter what I did. People reported no luck with Win7/8.1, either, for those two. But *now* they all work well with Win10, including Myst III and IV. I can't see why all the 25th-anniversary editions shouldn't run fine on Win7 64; GOG says that III and IV do--I just cannot remember the rest. You can go to the GOG store pages for each game and view the minimum OS requirements for the GOG versions.

My disc copies of Exile and Revelation have always worked on my Win 7 and 8 laptops. Intel GPU's even. 0 issues with IV, minor graphical issue in menus for III.

Another thing worth noting is that Real Myst (both versions) comes with Rime, a small additional age.