Mounting holes should be numerous, and the frame dust cover reinforced if at all possible. Less obvious, the frame and slide should be tightened for optimum accuracy. If not, the barrel, slide, and bullet can be pointed in one direction while the frame and sight are pointed in another. I take special pride in sight fitting, as with other accessory installations as well. The result is a neat job with no unsightly gaps and satisfied, repeat customers.
Some sights require welding or other pistol modifications.
Call about your interest. In general pistols with a firing pin lock will have to 1 pound heavier trigger pull due to the compression of the lock spring. To detect the differences, a side by side comparison is required. They are strongly recommended in the 1911 design. The 1911 handling can be improved in several ways.