I was tempted, but after some thought I ended up getting the regular edition instead. As others have said, $200 was just too much for the extras promised. I'd essentially get some cool extra x-ray pages, and some other fluff extras in the compartments on the front and in envelopes that I wouldn't necessarily understand since I'm just starting my journey into BattleTech lore (hence buying this book!). It also looked like a very unwieldy and giant thing to try and store somewhere based on the initial concept art.
I didn't follow the book updates (I didn't know there were any), so I wasn't aware that the Remembrance book was added later on. But after seeing the unboxing of the finished product, I'm glad I didn't purchase it because I think I would have been quite disappointed, especially since I wouldn't have known about the changes made. Instead of all the fluff materials (like the wedding invitation), it's basically just a "carbon fiber" box with a speaker, two books bound in an (admittedly neat) carbon fiber cover that matches the special Mercenaries cover, and some extra pages in the main book. That's definitely not worth the extra $150 to me.
I would be interested in the Remembrance book as a PDF at some point, though. It sounds like a very cool thing for older/established BattleTech fans in particular, and anyone interested in the behind-the-scenes in general.
All of the issues I described were with the special edition, not the Universe book itself. The book is fantastic and I haven't put it down yet.