I think they run half a size small. I would size up.
We have these:
My co-worker has narrow feet and she ordered her regular size, however she says her toes are thisclose to sticking out, but the arch on next size up was not in line w/her foot.
For me, I ordered my regular size and the straps are too tight, the next size up would have been perfect.
FWIW, lovemyshoes has horrible customer service and a loooooong return process, be prepared to keep them or ebay them if they dont work out.