Congratulations makd511... you will have some extras with Ainol V900, as it is a removable battery, surely a Nokia BL-4C, which can be charged out of the player and inserted when needed.
I have no doubt that manufacture of Ainol is better than my unbranded, ie: I bet that Mini SD slot house in a better way the card.
I hope that Ainol have solve some problems playing APE files. In my player ending APE playing of one song... the player get locked

.
Another good thing is that Ainol is publishing its firmwares. So you will have upgrades from time to time.
I will be pretty aware because Ainol is announcing support for FLV videos.
I hope you receive your player with firmware backup.