Danny I don't knowanything about PowWeb, but as one who has been involved in setting up and maintaining a similiar site I can only sympathise with your ISP difficulties. The host we used let us down at monotonously regular intervals, usually when it was most inconvenient (like when I went on holiday) and always without any notice. They would never apologise for their actions, even when they were forced to acknowledge them.
Does anyone out there know of a truly honest and reliable web host, because I am beginning to think the whole trade is run by shysters and cowboys.
Maybe there's a business opportunity here Danny for a web hosting service provider with some integrity to become the ISP of choice to the aviation sector.