OK, haven't had much chance to play with it yet, but here's my thoughts so far...

Hardware :
-Feels really nice and comfortable to hold once it's all together. It looks like a large device, but objectively it's only a little wider than a Jolla, and similar height and depth.
-Some online articles say it's got dual sim holder - it doesn't :-(
-Removing the rear cover feels like you'll break it.
-Screen seems really good, though I've not directly compared it to anything. The only mobiles I use regularly are Jolla and N900, so direct comparison would be rude and pointless.
-Camera seems to take decent macro shots (important to me, I tend to use the phone to document engineering details), and 1080p video seems OK.
-Battery life seems poor. Today had 25 minutes of phone calls, and a little wifi use. Battery has just hit 20% after 11 hours. (It's gone down another 6% while I wrote this, just because I keep switching it on and off to try stuff)
- No uSD card is a bit of a negative to me, though it is possible to mount a microUSB stick. FAT32, not exFAT (IIRC, I only tried a few things until I could read files off of the stick)

Software :
- Either the whole 'scopes' thing is a complete PITA, or someone needs to write some instructions for idiots like me. How the hell do I close an application? The only way I can find is to swipe into the 'portfolio' of scopes (usually 5-6 times until I can get it to stop onscreen, not select one scope) then slide all the extraneous apps downwards. Maybe theres an easy way I missed, or it becomes second nature, but it's been annoying me for 3 days.
- I really miss double tapping the screen to wake the device (Jolla stylee)
- The 'Today' scope is hopeless. Doesn't show enough information of anything, and spends a lot of of its time blank while (preusmably) getting location data to show sunrise time. Turn off geolocation and it just shows 'Sunrise:'. Irritating. The 'Apps' scope has buttons for 'phone', 'messaging', 'contacts' etc. and is much more useful as a home screen.
- I turned off the Today scope, for reasons above. Then I spent a half hour trying to find how to turn it back on.
- Lock seems to activate whenever the screen is turned off. I'd prefer 'after an hour unused' or something. I haven't played with the available options yet, this may be possible.
- Lots of stuff in the ubuntu store, but many (most?) of them are web apps... which just seems like marketing bullsh*t - is there a difference to just opening the web browser? I don't expect there to be many apps as yet, it's a new OS. I'd prefer to find a few decent native apps, rather than loads of disappointing web links. Who needs an Amazon app anyway? don't they have a 'normal' website?
- Bluetooth - cant make it non-discoverable. cant change device name. Seems buggy, took me 10mins to get it to connect to my car. Still can't connect to Jolla. Randomly finds/doesn't find devices.
- Facebook & Twitter integration - It has it, apparently. don't know, don't care.

I'm sure I've forgotten a lot of things, good and bad. I wasn't aiming to write a review, just point out the things that stand out to me. If this post reads as negative, it's not intended to. I have high hopes for this thing in the future... though maybe I'd like this hardware running Sailfish
Feel free to ask questions, I'll answer if I can... there doesn't seem to be much info online yet.