* You can build a usb installer using the utility here
* It is possible to keep One Touch restore working and nuke all of Windows if you're brave with the partition table
* Windows will keep booting until you remove the small partition no matter how many times you think you've deleted it - presumably the mbr is in there?
* The touchpad is a pain - you need to install the synaptics drivers and tune it there, but it will reset when you wake from hibernate. Found a fix for this.
* Hibernate and Suspend are easy to fix using this script
* Hibernate can be re-enabled in the power menus using this fix
* To save battery power, Bluetooth can be disabled on startup using the first answer here
Don't forget to install build-essential and synaptic packet manager. You want also probably want rcconf to update applications running at startup (command line tool). Finally, you might want to move the window buttons.
Unity seems quite good on the u300s. This isn't the first time I've encountered this environment but it's the first time I've not utterly hated it. The extra width on the laptops screen (over a standard 4:3 ratio screen) makes the left menu bar work - especially once it has been shrunk as far as it will go. There are a couple of oddities (such as some programs sometimes not appearing in the alt-tab list) which I hope will be fixed soon.
Note about the touchpad. This is the first modern (ie less than 7 years old) touchpad I've used and it took some getting used to. Sensitivity and cursor speed can all be configured in the synaptics driver menu obviously but it's worth mentioning the "disable touchpad on keyboard use" option. If you're using the keyboard to navigate (such as alt-tab) you will find this triggers the mouse disable regardless of the "ignore multiplier combinations" setting which is really annoying. Also, the mouse responds to taps thus:
* one finger tap - left click
* two finger tap - right click
* three finger tap - middle click (needs enabling)
Horizontal and vertical two finger scrolling can be enabled in the synaptics interface.