Again, I don't have enough experience / knowledge to answer your first question ... you might look up George Stringer, over in the Smithy section of TFL. I'll bet he is one fellow who can answer your question #1.
Regarding question #2, we practiced those drills in a Gunsite class, and the gun functioned perfectly. Others can probably give you more experienced feedback.
I do note that Hans Vang is holding a raffle of ... an 870 Super Magnum! See
http://www.vangcomp.com/firebird_raffle.htm
So, apparently he does feel pretty good about these shotguns. If you're willing to send some business his way, I'll bet he would spend a few minutes on the phone with you. He's a super guy, and very helpful to new folks regarding firearms. Just make sure you send him some business as a thank you for his advice. He does great work.
Regards from AZ