4:53 HAS BEEN ACHIEVED!!! There are a few quirks about this rom hack that make it very unique to run: You need a different setup other than sockfolder FPG in 1-1 to save the framerule, you can go directly in the World 4 pipe without having to load the warpzone, 4-2 needs 376 IGT pipe entry to save the framerule, BBG is more difficult and needs to be done differently due to different enemy bounce heights, 8-3 FPG can be done with 243 IGT because fireworks work the same way it does in SMB2J, and 8-4 needs to be played faster than normal due to extra loading frames between rooms. I would probably compare the difficulty of this time to a 4:55.2xx in SMB1 Any%. Either way, I am very proud of this time!
Played on Original NES w/ EverDrive N8 Pro
Following a few requests, a practice ROM for Super Mario Bros. Definitive has been released, which can be found under the Resources tab. Apply the BPS patch to version 1.2.1 of Super Mario Bros. Definitive. Enjoy!