In our 2008 and 2012 models the shower surround is as you describe a "PLASTIC" type materal that has seams with an edging and caulk in the corner areas. In both of our units the shower has worked very well but maintenance is necessary to make sure the caulk is adequate. We use our shower constantly in our RVs having lived in our units at least 4 - 5 months of the year. The showers have held up well but we did recaulk a couple of the areas. Sue
Thanks for the reply! You have the same size shower as I will have in the 3100. I'm 6' about 215, can I turn around in the shower? Will my head clear the skylight? I doubt if I can bend over.