I bought an M4 but the palce I bought it raised their prices and I know a lot of places sell ones that look like them. WHat actually is the M4 atty? Is it a EVO, M401 or is it just an M4. I am trying to buy a new one but wanted to see what my other options are out there. Also can you use the batteries on other Attys? It has the male threads on the battery.