Played and DMed it, have mixed feelings about it.
It was my first D&D and I didn't have much to compare it to (prior to that, my RPG experience was JRPG video games like Final Fantasy). I enjoyed it, but I can distinctly recall the allure of some of the options that AD&D had (class and race separate! Bards! Rangers!) and I was excited to move on from Basic to 2nd edition. However, in hindsight, I can now see the simplistic beauty of Basic that I didn't quite understand or enjoy when I was 12.
For me, Basic felt like a classic fantasy novel. It felt inspired more by young fantasy novels like The Black Cauldron or the Hobbit than AD&D's more "serious" pulpy stuff such as Conan or Chthulu. It was very archetypal: knights and wizards, castles and kings, dark wizards and their evil hordes. The mechanics were more steamlined-ish while still being compatible (and thus a few AD&D modules slipped into our play) and the monster selection excised some of the darker or weird-fantasy elements (demons, devils and mind-flayers) while giving greater prominence to dragons, undead, giants, and various animal-races. It's hard to quantify, but I can say it had a unique feel to it that felt more light, hopeful, heroic, and fantastical compared to AD&D.
That said, I'm sure part of my feelings are mixed up with memories of playing with the people I played with; where PC death was fudged out of existence and things like elves, trolls, and dragons were interesting and not old-hat. I'm not sure I'd want to go back to those mechanics per se, but I would love to see a setting for 5e try to capture the aesthetic of that 80's and early 90's high fantasy.