The North Face Sieve has some favorable and unfavorable attributes that lend it qualities more suitable to dry climates rather than wet climates.
I took them for a test spin in upstate NY in the summer after a light rain. I found that despite their "Hydro-Trak" insignia, they performed poorly on wet stone and rock. I would not recommend these for wet rock movement. Further, it was 24 hrs before the shoe dried out.
The shoe provides excellent ventilation, comfort, and asthetic appeal. They are lightweight and a pleasure on soft terrian where you can really get a feel of what your walking on. Despite their poor performance under wet conditions, I would recommend owning a pair for those hot, dry days. If you live in the Southwest U.S., this shoe is it.