Disclaimer: I own both a SL16 & SL24.
Definitely not a theatre board for the scene change issue. Probably not a good general rental board because it hasn't reach critical mass for market acceptance...at least in the US yet. In a few years, mark my word, they will be ubiquitous.
I previously had an LS9-32 and while I really enjoyed using it, in my market it took too long to turn a profit, even with cross-rentals. Plus it was overkill about 75% of the time. I originally shyed away from going the LS-9-16/01v + outboard preamp route because it just didn't strike me as very elegant. I was in the black with the SL24 in about four months.
That said- I love using these boards, have no issues with ruggedness if quality road cases are used and by definition it is a professional board because I keep getting paid. Have used it for a few national touring acts with nary a problem. Dialing in a ten wedge stage, on stage, by myself with the iPad remote is beyond easy.
I can't really comment on the durability in your climate but they are designed and tested in Louisiana.