Here is what I have found , first I cant leave well enought alone , if its an ARF WW2 plane I will tweek it as much as possible to my likes and appearances.
Second they are not as difficult to fly as all of the experts will tell you . So many planes have bad habits and warbirds get a bad wrap .
I have found that if you take all of the time on every plane ARF or built to do the following you will increase your success, however very few beginners in the WW2 area will do this ,
1) Proper balance , not just forward and aft but lateral -wing to wing .
2) Make sure all servos have rubber gromets to buff vibration , pushrods are locked with the rubber hose they come with , set screws are locked with locktight , engine is buffered for vibration , all hindges are pinned , yes pinned with tooth picks or screws, make sure servo rails are expoied in place (not Ca) because sometimes the gabs exist and will not make good contact . Seal every flight serface with clear heavy duty tape , unless your flying presision scale(and exact deatil is a factor) this will reduce flutter and the plane will fly much better. Make sure you have no play in the push rod bindings, take the time to support pushrods where needed. Relace all crappy kits parts (ARF or kit built )with better proven products like Dubro ect . Make sure your engine and wing incidence and all flight surfaces are set properly , and everything measures up . Run at leaset three tanks thru your engine so you have low reliable engine throtle . Get a very good battery charger and discharger and possibly (a little trickler ) for $29 bucks its the best investmnet I have ever made , my transmitter and flight packs have never been better . Make sure all flight serfaces move at the suggested distances and not more or less based on flight tendancies . Reinforces typical areas in ARFs and kits where you know there is high stress with fiberglass. Lastly always ask a ww2 expeineced pilot for advice on the plane and take -off, I have found take offs much more busy then landing , remember I said busy not difficult . Ok so why all of this prep , beacause most real planes have the above factors built in or they have a crew that maintains there flight readyness. Mots modelers will crash for years and never learn why they crash . WW2s are easy to fly in my opinion but they require the TLC that is sometimes is forgotten after the learning years, especially in ARFs.