Airport express better coverage compare to access point type?
Airport Express can be configured as an access point however the price is still on the high side.
It's actually good as an access point because of the limited LAN port, at least supports wireless N
I would rather buy 2 of airport Express and set it up as access point then buying 1 Airport Extreme because of the price difference and more freedom to concentrate on access point location.
Though the Airport Extreme runs on wireless AC, i think 2 times wireless N access point still gives better coverage and performance.