I use the Guest VLAN for guest wireless access and wired connections for media devices such as Amazon Fire TV, Apple TV etc.
I have found that the bandwidth (according to Netflix) is only 1M on the VLAN but I know I’m getting between 7 & 8M on the Main LAN. The poor performance makes the video strem flicker.
If Guests play games on via the VLAN then the media devices drop of the VLAN and the only way to reconnect them is to reboot the Surf Soho.
My speed tests vary a lot. Typical download between 6-12M and up load from .04-.35M. Ping rates are between 25ms and 60ms and jitter between 0-60.
The problem seems to be that on the guest LAN there is a delay in connecting to the internet which is long enough for devices to time out. Once connection to the internet is finally made all works OK until there is a long spell where devices aren’t used and then the connection problems reoccur. I don’t get this problem on the main LAN.