You’re right, of course - when they started it was Alphonso, they’ve expanded significantly I see!
I really don’t have a lot of breadth to my mango repertoire - my frame of reference for an eating mango is Alphonso so everything else falls short… among “american” (ie available here ) mangoes I only ever bother with champagne, the texture comes close even though the flavor is far off. Never mind any stringy-flesh mangoes. I’ll splurge on Alphonso in season, if i remember.
The flavor of different indian (and Pakistani, I’m sure, though I’ve never eaten one) varieties is very distinctly different, it’s interesting. For pulp (thicker than juice, eaten with a spoon as part of a meal), there are special varieties.