*Symbiface 3 possess an onboard mp3 player. Are we still talking about Amstrad CPC here?
*Albireo provides low level access to internet via SLIP which mean having the IP stack on the CPC side instead of it being done by the peripheral like in the M4 board, and having a bridge server on the other side. So it is not convenient at all. Also, the Albireo does not provide RTC functionality, which means another peripheral is needed for it.
*M4 Board is [https://unidos.cpcscene.net/doku.php?id=en%3Aannexes the fastest measured solution for mass-storage on the CPC]. It is a very complete and convenient solution with NTP-based RTC and Wifi network and very future-proof. But that means sacrificing pretense at historical ressemblance pretense as the M4 board does all the hard work regarding the filesystem and network protocols for the CPC. Support for the Internet stack could not have happened during the commercial lifetime of the CPC anyway, so does historical pretense matter for that kind of stuff?
The dilemma is that emulating multiple mass-storage and network solutions mean fragmenting the already small CPC community and so having less compatible CPC software and bringing complexity and confusion to users. So a choice has to be made. Currently:
*The M4 Board is emulated by CPCemu