For a number of years, RIS was the standard rail type for airsoft, but recently more and more gun manufacturers are opting to put KeyMod rails on their guns, in lieu of a Rail Interface System (RIS). KeyMod is more of an updated rail system for guns, but there are pros and cons to using this system when compared to RIS. I will lay out some things in this article which will hopefully shed some light on both of these rail types, so you can make an educated decision.
First, the most obvious difference is going to be the accessory compatibility; RIS accessories will not fit on your KeyMod rail, and vice-versa. However, KeyMod makes RIS conversion rails which attach to the rail to add an RIS rail segment. This will allow the user to utilize his/her RIS accessories. Of course, you can just buy KeyMod rail accessories, but not only are you buying double the accessories, KeyMod accessories can be pricier than RIS attachments.
If you were to compare KeyMod and RIS side by side you will notice that the KeyMod is going to be much slimmer than RIS. Also, KeyMod rails are generally lighter than RIS rails, because there is less material. If you were to grasp the handguard of a gun with an RIS rail then grasp a KeyMod, you will feel the difference; in my opinion KeyMod fails feel much nicer because the rails are not sticking out. I would describe KeyMod as a “clean” look when compared to RIS.
There is no denying that KeyMod is here to stay, and more manufacturers will continue to bring KeyMod guns, rails, and accessories to the market. As a society, we always follow the current trend, and the trend is definitely KeyMod for airsoft. There is always going to be an element of personal preference in the KeyMod vs RIS argument, but overall I believe that KeyMod does hold an advantage over RIS.