Strengths: Lightweight, foot position, great looking
Weaknesses: Toe box seems a bit tighter
Overall: Having had Guide 3's & 4's and liked then it was natural to go for this cool looking new shoes and must say I'm not disappointed.
I could immediately feel my running style change from pronounced heel strike to a more central foot (which I'm lead to believe is more efficient). Took a bit of getting used to but, I don't know if it's the weight, the change in style or pure coincidence but my times on training runs have got quicker without any perceived increase in effort.
And on a totally non technical note I love the blue / yellow colour scheme (you have to run faster in these :-) )