Worst quality ever - XS Sight Systems DXT2 Big Dot Night Sight - Glock

The rear sight was not illuminating when I received it. So I contacted XS Sights and they replaced it for me promptly. A few months went by, then the front sight stopped illuminating so I contacted them again and they sent out a new front sight. Fast forward 6 months and what would you know the front sight not illuminating again. They sent out another front sight this time I never installed it I put it in the safe and not even 3 months later it doesn't illuminate anymore. Their customer service is great but very poor quality products. This is a purchase that I regret and should of got the hint when I received the first ones that didn't illuminate.