Is the 802.11g modulation type that much better that 802.11b?
What are the chances an ?¡é?€??a?¡é?€?? network will perform better in situations where there is other
Networks in the area or where mutli path or a fade situations are a issue with ?¡é?€??b?¡é?€??.
Unless you need backwards compatibility with 802.11b devices, 802.11a should give better results. 802.11a networks allow 23 non-overlapping channels and have fewer sources of interference in their spectrum as well as not having the protection mode problem. 802.11a was released prior to 802.11g. People using b wanted the data rates of a with backward compatibility with b. The downsides to a are smaller coverage area due to propagation of the higher frequencies smaller wavelength and the cost of adding more APs to cover the same area. You may also argue the lack of backwards compatibility as an issue. However, I count that as an advantage.