We're almost through the 2nd summer now, and it's still ok - no corrosion damage.  I leave it out in the rain, with the vents closed, and it seems fine.  It's great with the hardwood lump charcoal for steaks - sear over the high heat, then smoke indirectly, covered, away from the heat until desired temperature (a remote readout thermometer helps).  Indirectly with a Smokenator I have make many pork butts and beef rib roasts.  Quality equipment, this.