I will go along with you on some of your points but a rear carb is a pain to get to. If you have a boxed in firewall (most large planes do) you need to remove the engine to do carb work[:'(]. As for "spitting" I've never had one do this. I do have two reed valve engines but they are twins. My three singles are piston port and run super. I must add though the single cylinder engines have the carb inside the cowl, this does make a big difference.