Originally Posted by MyLastRook
Not me. I'd stick with the model you already have ordered.
Since your stated objective is home defense. You'll find that 2" and pound and a half of steel and ammo hanging off the front of your shotgun really does make a difference in target acquisition time as you pie a doorway or corner. The shotgun is the most viscous of CQB weapons. He who accurately shoots first with the shotgun at close range usually wins the fight.
Having run Standard Mossberg Ghost Rings on both the 20" and 18". I can tell you the the good old Standard Orange Ramped, Winged Mossy Ghost Ring is...Fast Fast. As fast and accurate as you'll ever need. A tritium front is available should you so desire.
You can also get a one shot extension for the 18". For 6 in the tube.
It's been my experience that the 18" are just a whole lot easier to maneuver and carry for any length of time.
If you need a light (and its a good idea) get a surefire forend and skip the cheap ass Mako forend and goofy Bayonet lug crap. (As well as the goofy wanna-be Blackwater contractor paw print logo. which given how all the much bally-hoo'ed contractor B.S. turned out in the end. Is not really something I'd want on the side of one of my weapons.)
It's (6 shot) actually only 1.5" shorter, 18.5" barrel.