depends what you want to use them for & how important relaibility is to you. to get into eotechs & milspec aimpoints you"re looking into the $500 range but you get very long battery life, hight relaibility and shock resistance. go into the hunting aimpoint/holosight range and its around $300 with the same dots but mayber a little less bulletproofing. $200 is the bottom i would use as a reasonably reliable and bright red dot as long as you keep it simple ie stay awaty form variable reticles and the like - (more to go wrong).
FWIW