No expert but used Discord Server for small group and it was so so ...
Used it for a large group (200+) and it was fine.
The amount of money to get it useful was a tiny amount ... at least it was at the time.
IronRed was having challenges because of a local issue with his WiFi. The service would not matter if his connection is degraded. Discord, Roll20, or Skype would behave the same.
IronFred seems to have issues with his drivers or perhaps his local connection. I have only half listened to his woes but he has a computer tangle. I'm guessing he has a unique configuration causing conflicts.
Discord had a lot of neat features ... including push to talk and being able to change the volume for each user individually.
The worst part of Skype seems to be that it patches too often.