I am planning on buying a Glock 19 in the near future (my first Glock). I want one with night sights. Would it be best to buy one with factory night sights already installed? Or should I get some night sights put on after purchase? What brand name night are factory Glocks? It would seem cheaper just to buy a Glock with the factory ones already installed or would this be an unwise move. I dont have night sights on any of my gus so this whole night sight thing is new to me. Any feedbak would be great.