Langra Banarasi was bland for me. Size was almost Cushman like and taste wise it reminded me of some grocery sold mangoes. *Bleh* The tree also is extremely vigorous but seems to hold lots-o-fruit to maturity. Kesar is nice. Fernandin is a very sweet white fleshed mango though they are on the small size (Neelam-ish). Gorgeous external skin coloring though.
Last year was first year for my Langra to fruit. I got lots more bland ones that year
But this year I was getting more flavorful ones...maybe due to the very dry spring. I was getting some that were a 7.5 or an 8.
I would not write off Langra as bland. The fruit seems variable and on the plus side (as you mentioned) it is a good reliable producer and a vigorous tree. Lots pf family and friends like bland mangoes
OR it not a big deal to them. A mango is a mango and they are not going to prefer sweet-tart over Langra. Its all the same to them. Another plus is Langra is a large and good looking fruit and many eat with their eyes.
Langra is a productive tree so I will never axe it even though there are more delicious mangoes