My experience has been hit and miss...
I own one for each car and Jeep that I have...
The first one I purchased ( most expensive and poorest quality) was a Micro Start by Anti Gravity Batteries. I paid a fair bit more for it but figured it was a quality unit. My mistake. I had to exchange it twice due to a swelling battery that swelled so bad it cracked the case. This happened when it was unplugged and sitting on the shelf in my garage.
It was like pulling teeth to get the unit replaced under their warranty. They certainly felt that they were doing me a favor in replacing a defective product that became a fire hazard well within their warranty period. - However, third time was a charm and I now have a fully functioning unit.
Like a glutton for punishment, a few years later I bought another based on good reviews and giving the benefit of the doubt that they may have improved their product, and so far so good.
However, I also purchased an “Aickar” brand from amazon for about half the price of the Antigravity Micro Start and it will crank a dead as a door nail 1970 Nova with a 350 or spin my TJ 4.0 like a top.
This experience leaves me feeling like the batteries are not much different based on brand name. The cables between the two kits are of equal quality. The extra I paid for the antigravity micro start name did not translate to a better product or better service.