A lot depends on the use to which the pistols are put. the little tasco dot soghts are great but they may no longer be available as tascos. they are still available thru Brownells under a different name. They are tiny, and battery life is tremendous. they will withstand the shock of living in the rear sight dovetail of a 1911 45. Drawback? they are a bit costly... No eye relief and auto brightness control.. They weigh less than 1/2 OZ and are less than 1 inch tall...