Submachine gun, is different than a PDW, figure out what you want it for.. then decide what you want.
When ever someone says submachine gun, I think MP5 -- if you go AEG, go there, Cyma seems to be making very solid ones in your price range.
MP7- GBB - KSC .. also WE ( though I don't own one of these yet to say anything about them)
CAPS Range Officer
Toronto Downtown Age Verifier
If the tongue could cut as the sword does, the dead would be infinite