I did alot of research before purchasing and installing my 300x2. There was a time that the 300.4 were overheating, but the that issue has been resolved. As far as the draw, I dont ever put my bike on a tender and have not had any issues since installation (June-ish). I have my amp wired directly to the battery (neg/pos). And if i remeber correctly, the amp has technology now that only allows the amp to turn on when it recognizes the radio is powered up- might wanna confirm that with fosgate. BTW, my unit is mount on top the the radio secured with industrial velco. NO issues.