After reading yet another review (and this was a detailed one), I still have found only a single show-stopper problem for myself: That it's not possible to let the mail client download headers only. This means I will not be able to use the device the way I had planned. There's no way I can let it download the tons of mail I get, through the phone connection. It will be inconvenient enough on wi-fi connection.

Hopefully this will be fixed (there's an open bug in bugzilla about this). Presumably the mail client is open enough that it's possible to rebuild from source - if necessary I will have to look at this myself.