Difference between Tudor Submariner ref 75090 and 75190

[dajiggalo]

I just recently discovered the mini-subs from Tudor and trying to do some background research before I pull the trigger on one, sooooo.... does anyone know the main differences (or can point me to a good reference) on the Tudor Submariner 75090 and 75190? Years made? Movement upgrades? Design differences? I tried going through the reference section of this forum, but most of the posted links are dead, and google just came up with a bunch of "for sale" links. What I can gather so far, they're both about 35-36mm with date functions. I've seen mostly black or blue dials w/ matching bezels, w/ tritium markers... but I've come across a few with the markers in white-gold surround (like the current Rolexes). I've even found a few with stainless steel bezels and one with a white dial! Are these legit? any help would be greatly appreciated!