Wanted to do a 100% Classic/No Major Glitches in Metroid Famicom Disk System.
There is probably another minute or so of timesaves with my current skills, so will see later if I go for sub-55.
With NGC port loading times between areas this is a 55:23.866, from the first frame in Brinstar to Samus first frontal frame on Tourian exit elevator.Played on Mesen 2.0.0 using FDS BIOS.
57:49.770 if going by Famicom Disk System loading times according to Avidemux.
(Each of the seven loading times according to Avidemux: 23.656 + 23.672 + 23.656 + 23.656 + 23.656 + 23.672 + 23.655 = 165.623 (2:45.623)
Assuming each loading time in NGC Metroid Prime port is 2.817: 2.817x7 = 19.719 seconds.
So 2:45.623-19.719 = 2:25.904 of loading times to remove.
Thus, 57:49.770-2:25.904 = 55:23.866).