Looking to buy a emulator sourced out an APU1 from moates seller has two to choose from, asked him to open them up and one has a battery in it does any one know which version is better? or what the differences are between these?

 

I think the coin style battery will be cheaper to replace might be the only difference

 

how does the other unit without battery get power?

 

the emulator is powered by the nvsram