Done properly, I wouldn't hesitate drilling and installing studs in your new stock. Heck, I have some bolt action stocks that cost almost twice a regular handi full cost. Thats for the for the wood alone and they have studs in them...
Like Tim, I have tried the stock shell holders and didn't like the feel or weight on the stock. I really like the 5-10 shell wallets that fit on your belt. Most of the time I don't put them on my belt either. I have a shell in each of my front pockets and that cartridge wallet in my pack as back up storage.
CW