The problem, I have heard, with the 410 is the tight pattern. For young shooters, if it isn't fun, they won't want to continue shooting. The 410 throws such a tight pattern that the MISSES usually out-number the HITS. Every time they see that Clay explode in mid-air it builds their confidence and makes it exciting and enjoyable for them. If the youngster is big enough to handle the 20 ga then I would go that route. If not, maybe starting them with a Modified 410 barrel would be the answer. By Modified, I mean, take a 26" (adult length) 410 barrel to your Smithy and have him take it down 2" to a 24". This will open it to cylinder bore so the pattern is bigger to get'em more hits than misses. Once the confidence is there and the proper form has been developed graduating to the fully choked 410 or a 20ga will be an easy transition. Just my 2 cents.