Thanks for the reply on both the kick and function of the choke tubes. I know what you are saying, I push pretty hard in some areas, but he likes to hunt and shoot, so I'd rather give him a little leway to figure it out himself. He's only 11 and 75 lbs, I figure by summer he should be 8-10lbs heavier and perhaps have more self confidence.
But your advice about the 20 and slugs pretty much solved that issue, I won't be attempting to go that route and spending money that really won't be worth it. If he wants to hunt deer, he's just going to have to come around on the 7mm.08. If not, heck he can still be a happy small game hunter for a few more years. Deer hunting isn't everyone's goal in life.