They must be good guns. They are simply good quality. Well, could be. There are, of course many other choices such as Stevens, Ballards, and Remington rolling blocks and Hepburns. The choice is dictated by availability, aesthetics, and why you're shooting.
Caliber is the next consideration.
Since many of us are involved in silhouette shooting, we must consider what caliber is needed to do the job, and it is the extreme that must be considered, the 500 meter rams, and the 200 meter chickens. We need a caliber that will buck the wind well enough to hit and knock down the rams but still be shootable offhand at the 200 meter chickens. As to which .40 is best, remember that brass availability and cost are factors. There are many other factors to consider in choosing a rifle and a caliber, but since so much is a matter of personal preference and opinion, I would encourage you to ask around and experiment. Future articles will deal with various guns and calibers in more detail.