The sigelei is the most annoying. The button just went crazy. Sometimes it fires, sometimes it doesn't, sometimes it goes into menus by its own. It's maddening finding that the wattage has suddenly gone down for itself, or, the out is off. Mine is a Telemax.
As for the Gripper, I blew the center pin. My hubby fixed it with a retainer, so my attys don't screw all the way down, but at least it makes contact and works!
Shame about your Sigelei, I have five Sigelie's and not a problem with any of them. But I am glad to hear that you have something. Two things stand out,
One, don't overtighten anything, especially juice delivery systems, this can push the center pin down.
Two, juice and electronic circuit boards don't mix.
Although I am sure you are aware of both of these, it may help someone else.
Here is hoping your problems are behind you, and happy vaping is ahead. Once again, Best Wishes.