I appreciate all of the replies! Clearly I was already leaning towards the Mist King, and will be purchasing one next week. It sounds like I will be fine with the Starter level. The less I spend on the mister, the more I can spend on orchids

Any advice on number of nozzles?
About construction of the case, the bottom has about a 2" pan we created by nailing a piece of wood across the front with a piece of metal over the top for extra protection. We stapled, then siliconed (with orchid safe stuff, of course) a shower pan liner in the bottom so it holds water. We siliconed in the plexiglass panels so they are water tight. The top has a thicker plexiglass panel so it can hold equipment up. Also I removed the back panel and replaced it with plywood that I stained. I figured in the future, if it got destroyed, I could replace it. All of the interior surfaces are coated with polyurethane for outdoor use, and also I coated the back side of the plywood to prevent warping. Just another small project I roped my husband into helping me with

It's been up for about 3 1/2 months, and so far, so good - water beads off the surfaces.