Ranked in these QuestionsQuestion Ranking
Pro In-game overlay shows who is talking
Razer has in-game overlays which show which player is talking. this can be very helpful when playing with acquaintances or other players who you can't recognize by their voice alone.
Pro Chat rooms can be shared with voice chat users
To talk to others you will need to join a chat room. Then, from within the chatroom you can enable voice chat. This allows users with voice chat to still communicate with other users who don't have access to voice chat, and voice chatters can still type in the same conversation as the other players (both with and without voice chat enabled).
Pro Windows and Android apps
There are apps for both Windows as well as Android. This is beneficial because if you have a poor internet connection or low end hardware you can run Razer Comms on your Android phone instead of your computer, freeing up all the possible resources to maximize framerates in your games.
As a side bonus, you can keep chatting with your gamer friends even when on the go using the Android app (provided you have an Android phone of course).
Pro LoL Scouter helps your League of Legends game
LoL Scouter gives you information about your opponents, including how much time they've played their character for. This helps you gauge how good they are, so you can plan accordingly.
Con No support for Apple or Linux
If you have a Mac or are using Linux, you can forget about Razer Comms. It's unlikely Mac or Linux will ever get official support as Razer is traditionally a Windows-first company. This goes for iPhones too, while Android has a mobile app for Razer Comms, there is none expected for iPhones.
Con Not well known
Most gamers already have their preferred voice chat program, and getting them to switch will take some real convincing. Razer Comms isn't well known, and isn't very useful unless you know at least a few other gamers that use it.