I have two 870s and was wanting to SBS one of them to a 12.5 barrel. My options are a 870 Express Magnum or 870 Express Super Magnum. I like the option to use 3 1/2 inch shells and would have the barrel cut down and rethreaded for chokes/door breacher. The other (non super) I would buy a new barrel and do the same, CDNN has 870 barrels for $70. What are the pros and cons for both? Paper work is almost done, just need to put the final touch to it for what reciever I'm going to use.

Thanks!