Sorry, I am late to the party on this and I do hope you have ironed out the issues with your subtank. It sounded to me like the coil was not primed enough. I hope you stuck with it as the Subtank is an excellent tank and easy to use. You could of also got a bad coil. I just picked up the sigelei 75 and I love it. I may grab the Sig Mini 30 for a stealth device at work and I am looking to pick up an a decent mod for my brother who is new to vaping. I would be interested in hearing how yours has held up
