All of these are good. The type doesn’t make a huge difference- the ripeness is more important.

There are minor differences in sweetness/sourness balance, and strenght of the flavour. But all of them are good mango. Except the R2E2, it’s is exceptionally flavourful, almost pungent, very sweet and very smooth flesh. If properly ripened, it’s like the durian equivalent of mango. Serious.

I prefer to choose mangos that are evenly coloured and got no dents, blemish, bruises or holes (you want good ones to slowly ripen at home). Don’t need to be very yellow, even green with a slight bit of yellow is ok. Bring that clean and smooth baby home and let it ripen in the kitchen (put on something slightly soft like some newspapers You kids may not know what newspapers are. Before the internet people had no way to communicate, so we got our updates of the world affiars via centrally broadcast video on TV, audio on radio, and printed on newspaper. There was no such thing as customised news or media back then. it’s a bit like making your own bread I guess, it’s not as convenient but it’s… ). If you let it ripen slowly the inside and outside will ripen together. Be aware that this process may take 1 or 2 weeks, so just cut it when you think it looks done. If the mango looks like its starting to develop dark spots, immediately put it in the fridge and let it ripen until you feel the spots are going the be more than skin deep, then just cut it before the blemishes spread into the flesh. I like to turn the mango every few days so the part sitting on the table doesn’t get too soft. Like coma patient, you know.

Once it’s ripe (smells nice, soft when pressed, yellow like proper mango), its ready to cut. In this condition before cutting, it can keep in the fridge for a few days before becoming over ripe

Local or Thai R2E2 mangos that look ready-to-eat are sometimes ripened with carbide (or similar thing applied from the outside). This makes the skin and top layer of flesh fragrant and soft and orange, but inside it’s still hard and sour. If you’re not sure about the fruit ripeness, buy a green one and ripen it yourself as described above.

R2E2 is an Australian type of mango, now they are also available from Thailand. The ones in Australia are HUGE, very yellow and very sweet. IIRC the fibres are also very short, so the flesh is very very soft and smooth. Some people like it, some don’t. It’s got a very striking name and reputation, so they are generally more expensive. I don’t buy them unless the price is really good and the fruits look like they have potential to ripen at home.