Hi, I am currently in the market to buy a shotgun mic for on site dialogue and sound effcts in post ( both for filmmaking). I have been recommended a Sennheiser me66 which varies in price from $400-700. Would you guys suggest another microphone instead of the me66?. Are there any key things I should look for? My budget for mics is only $500ish or less as of now. Any help would be greatly aprreciated

Thanks,