The 870 in my 7th favorite shotgun in my safe. Being number 7 is not a good slot. So that makes it prime for trades or wild modifications.
This specific conversion kit doe not cost overly much at about $350.
I have an upgrade grip, a drop fore grip and a tactical light already and waiting.
Here is a feature list from the website:
Designed to accept a wide variety of aftermarket AR-style accessories
Familiar AR-style grip and safety Split-trigger for increased safety
Variety of rail mounting areas for tactical accessories
Super-smooth and contoured slide release area
Rugged shell deflector for left handed shooters
Ergonomically shaped and easy-to-grip slide forearm
Generous access to loading port
Conversion assembles easily with tools provided
Easy to follow conversion instructions included
Multiple ambidextrous sling points for 1-point and 2-point sling
Field strips with tools included under butt pad
Manufactured from rugged, hi-tech, molded materials
Features an easy-to-grip, non-reflective surface texture
Does not in any way alter the original shotgun
Overall thickness: 2.75, width: 8, length: 28