I'm looking to upgrade from my 510's and 901's to a mod. I have went through all 3 versions of the dse905 and they all seem to short out after a few days of use. My friend let me try his Screwdriver mk1 and mk2 and I didn't like them either. So although I'm not super new to vaping, I am new to the mod world and looking for something dependable, somewhat enexpensive, and the battery life will last all day. I'm a full time fireman and don't get much time to charge batteries while at work and don't want to be stuck without my e-cig. Any suggestions on what mods I should look at or personal stories would be more than appreciated... Thanks...