I think the warm/hot water can be ok for some MSers. I dont normally have a problem with heat unless it's insanely hot outside, but if I've got a weird flare going on (usually a visual flare) the heat drives me bonkers.

I can tell when I've got inflammation going on somewhere, because I'll either get a l'hermittes when I bend my head forward, or taking a warm shower or bath will set off some numbness.

If I'm not flaring, I'm fine with hot showers (love them in the wintertime)

I do try to be careful with hot showers, because sometimes I dont know I've got a flare coming on until I take too long of a hot shower.