Originally Posted by nhluhr

"Conclusion
Even the best rim designs and intentions can be negated by poor spoke choice. Round spokes offer very good strength and fatigue performance, but hold a substantial aerodynamic performance penalty and should be avoided in high performance aerodynamic wheels. The aerodynamic power differential between round and oval spokes is sufficiently higher than any possible weight savings, equating to tens of pounds of additional weight to the bike, so round spokes should be avoided regardless of weight advantage."