So I've got a 12ga 870 express super magnum synth 26" barrel The main two things I want right now are pistol grip and mag extension. I like the pistol grip with folding stock idea and been looking at the ATI top-folding one. Any good? Just under $50 here: http://www.combatstocks.com/ATI_Universal_Top_Folding_Shotgun_Stock_SALE.cfm As far as the mag extension, I'm thinking the 8 or 10, but with the 26" barrel i'm not sure if the 10 will be longer than the barrel or not. I also read on some site that newer 870s were manufactured with two dimples that make it more difficult to install the extension. I'm sure I could grind them off, as some have done, but i was curious if mag extensions were typically easy to install on 870s. I'm pretty technically inclined.