The 836L is just like the 826 however it does has faster WiFi connections. So if you don't have any devices that support the 450Mb WiFi, then it would not be used until such time when you got a device that could. I presume the CPU is about the same, just the Wifi is different.
You can see the table picture graphic of an overview of what each L model router does. Even though it's not mentioned that the 826L is ideal for gaming, it seems to be and works well.