Ok, got mine as well today. Don't have to much time at the moment. But did of course some tests.

First objective impressions:

Even so it is much thinner than the N900 (the whole phone is just as thick as the keyboard part of the N900) it is a quite big and heavy phone. I didn't expect it to be different, anyway I would have preferred a smaller (not thinner) phone. For my hands it is not that easy to reach every button on the keyboard. But I think I get used to it. On the other hand being thicker than the XperiaX I use at the moment makes it much saver to hold.

Build quality is excellent. The only things to criticize:
The slider snaps in place quite hard. I hope it gets a little bit softer with time. The keyboard backlight is - like it was already reported - a little bit uneven, but who cares.

All things I tested worked fine. Sound of the phone is very good (earplugs and speaker). Camera quality with stock android camera app seems to be good. Screen is bright and you can dim it down quite low.

The biggest let down on the Pro1 is the OS. Android feels just horribly wrong. I wanted to start the notes app, just to test the keyboard. But you can't do that without having a google account. What the hell....

I hope I will find some time on the weekend to flash Sailfish on it.

Thanks to chen and his team! They did a great job!