I'm now using the ALTI-2 for a while, and man, I regret spending that much money on it.
First: there's no option to turn the unit off. It means that, even thought the battery is rechargable, you may find yourself without juice if you only jump on week-ends (like I do), and forget to charge it on Friday night.
Also, the good diferential for logbook options is crap as there's no way to add/edit the DropZones and Aircrafts. Also, no way to export the logbook from the ALTI-2 to my PC (unless you pay extra for Paralog software, which, as I read, it's not guaranted to work to upload data into ALTI-2).
Also, tried to contact Atlas a few times, without any reply..... :-(