PostmarketOS vs Manjaro on Pine Phone

[dRateNWAytORy]

While I ordered a Pine Phone with Manjaro, I received one with PostmarketOS. Since this is the first time that I am using the Pine Phone and I am indifferent to which particular flavor of linux I am using, I was wondering if someone could give me a brief summary of the differences between the two operating systems to help me decide whether I should flash the device or keep playing with PostmarketOS.

Thanks!