I am pretty much in agreement with many of the posts above.
My preferred version is 4K77, Empire Strikes Back Despecialized and 4K83.
The one thing I would add, I LOVE the way the sound options are done on the Despecialized editions.
I love that you can choose from the mono, 35mm stereo mix (the most familiar one) and then Hairy_Hen has created an approximation of the 70mm six track mixes.
I love having the options, but Hairy_Hen’s six track approximations are awesome. They were bigger and boomier and it was like seeing the movies again with a new exciting element. If you have the sound equipment to take advantage of them, they are worth watching just to experience those tracks.
I am not sure how the stereo track on the blu-ray versions of 4K77 and 4K83 compare to the ones on Despecialized. Not sure what the sources are.
But, the Despecialized gets points in it’s favor at least for those tracks. The good news is, you now have options available to see the movies.
May the Force be with you.