I haven't had the chance to try the Slot-Lock, but I've used a lot of Cheyennes and have spent a couple thousand on T-Techs in the last few years. I've never had any issues with T-Tech. I will say from the photos on his Instagram, the Phuchstyx needles are very different in look/design than T-Tech. They have a more angular shape to their liners, and their mags have a little bridge of plastic holding the mag in place.