It's got an AL32400. At least my exemplar, I have removed the heatsink once.
Also you normally don´t have to worry about the lifecycle of a Mikrotik product. Almost everything they released since they were founded is still usable and you can install a currently supported RouterOS version on it.
One more addition, as I've just seen the addendum of the review mentions that there is almost nothing in the user manual: the Manuals in the Mikrotik world only describe HW specific quirks.
You have to go to: help.mikrotik.com
Then study it for a few hours, days...
