I don't know that particular model of Wheelsmith but presume it's one with the new style wider rims. I usually ride with Velocity Aeroheads and find them to be good on my C40s. I also used Campy Nucleons (Neutron with silver spokes) on my 95 C40. They're 10 years old and still one some bike of mine. I find I like the wider rims (Velocity A23 in my case) on my Extreme Power and EPS because I can run them with less pressure and get a better ride. I haven't tried them on my C40s though because its ride is a lot less jarring than the newer frames and it's winter so can't really do it now.
If you're looking for a deal on Nucleons, try Ribble (www.ribbe.co.uk
I think). I got a set from them a few months ago for my Wilier and their price was great. Delivered in about a week from the UK to Canada.