My rule of thumb used to be, when making the weight vs cost trade-off was, that I would spend up to a dollar per gram saved for static weight, or up to a dollar per 1/2 gram saved for rotating weight. I'm less concerned about weight nowadays - I need to lose 15 lb off my arse before I start obsessing about bike weight. But, my comfort levels are not yours, and if you have the cash and the wheels make you feel good, go for it.