I've read various things, but couldn't find anything definitive. Just got a new Sigelei 150 in the mail, along with 2 VTC 5's. My question is, do I need to use these two, and only these two batteries with the device from now on? Can you not mix and match batteries with these devices? I have several more VTC 5 batteries laying around, but I ordered these two specifically to go with the new mod. Anyone have some more detailed info about this? Thanks.