I stick it in there for a couple reasons. First, the icon says "spit" (same reason I stick the seafire in the "spit" category). Second, for most people they are for all intents and purposes the same plane. An La7 going against any spit fights the same way, it has the same advantages and disadvantages over both. In some cases, a plane will have an advantage over a spit 5 that disappears when it faces a spit 9, but that it fairly rare.