It is unfortunately the case but you must remember your one of only a relatively small number of racers the who have discovered the joy of Kyosho ownership, once the rest work out they are the only car to have then stocking levels will improve to where AE is ect. today. Remember it's their loss not yours
Seriously though I've never had to wait very long for Microtech to get me anything, certainly never missed a meeting due to lack of parts.
It is also worth remembering that as Kyosho are always aiming to improve and update their parts it is actually better to get parts from somebody who keeps regularly rotating it's stock such as Microtech as you will always be getting the latest greatest bits.
Let me know if your ever in need of anything in an uber hurry as I keep pretty good stocks of the majority of parts in my box and would be happy to send them out if you arrange replacement of them to me via Microtech.