I don't have a Lance, but I have sliding windows. I'm not sure how I would have tinted them (well, dw did the work) if I had the jalousie style. Also, the mechanism seems to be more complicated with the jalousie style.
With respect to rain, if it also has wind, I don't think you'll leave the windows open. We have ours open for the Northwest sprinkles sometimes but never with the windy rain. If there is a slight wind, we just open the down wind side and use the fan.
As far as buying one goes, you should check with some remote dealers if necessary to see the price range is reasonable or not.
