Relatively easy to put together on my own (probably easier with two people) and took about 1 1/2 to 2 hours. 
Instructions are not great, my tips would be not to put the plastic slat ends into the frame sides when the instructions tell you to as they either fall out or (worse) get stuck in the frame during the rest of the assembly. They can easily be put in later on. Remember the slats are curved and should curve upwards, not downwards.
Also, don't tighten the cross-member bolts too much as the cross-members are made of thin metal and will deform easily - they have a hollow square cross-section, you will know them when you see them. 
For heavens sake don't use the feeble spanner that comes with the bed!
It looks great all set up and seems comfortable to me.