Has anyone tried the MagGuts.com +1 magazine kits? Are they reliable? Mostly wondering about the ZeeSpring™ and longterm durability in the Glock 43. That spring design has my interest, not sure because it's new and no track history yet... sharp bends are usually weaker compared to traditional and gradual round bends. The follower with 2 upward pointing tabs also looks potentially problematic. Any thoughts on these?