I played it and I liked it. We played it instead of BX and BECMI and even had arguments with others about it. (we did use Mystara as a setting though sometimes). It was a mess of rules and we'd literally sit and read the books to find rules and subsystem we didn't even know existed earlier while it wasn't our turn. That sometimes let to campaign changing events as people rolled for psionic, decided to get henchmen or hirelings, or buy magic items. Everybody pretty much moved to AD&D2E though without issue or tears.
I still end up in an 1E AD&D an ongoing game every decade or so. Some for fun. Last one was specifically an attempt to play RAW. Later, a read through of the 1E DMG revealed some rules we missed as we had no idea they were even there (and lots you figured would be, but aren't). Still like it better than other games like Castles & Crusades which left me wanting to either play 1E or 3E but not C&C.