I find AD&D better than B/X—arguably twice as good. But it also comes with five times the page count (and weight, price, etc.)
In some ways, it’s like a burger that’s twice as tasty or has twice the protein of a McDonald’s burger, but also five times the calories, five times the cost, or stretches your lunch to two hours instead of twenty minutes.
Maybe there’s a better analogy out there, but you get the idea.
So let’s stretch the analogy a bit further: AD&D also has several parts (bards and monks, weapon versus armor, weapon speed) that people will simply remove from their burger before eating. Meanwhile, B/X might lack enough protein for your diet, so you can just add more meat or a second source of protein.
Which do you prefer?
Most OSR titles, including my own, try to reach a happy medium between the two.
Often, they start with B/X and add races separated from class and a few extra classes and magic items.
I believe my ideal D&D would be AD&D reduced to around 120 pages like B/X—cutting some fat and carbs from the big burger instead of adding more meat to the small one.
I don’t think this has been done successfully. OSRIC gets close but not quite (still way more than 120 pages compared to B/X, and it doesn’t even include all AD&D parts). The Challenges Game System by Moldvay could be a good start. Every edition of D&D after B/X, including 2e, 3e, and 5e, tries to streamline things without actually simplifying much.
Maybe I should give this a shot before my next campaign. While I don't, you can read my analysis of the AD&D DMG here, including many thoughts on how to use AD&D stuff for your B/X games.
