Hi adrianmarsh,
NOP! your wrong QOS would only get in the way of VPN connections in my opinion by significantly reducing the available bandwidth required for VPN to work.
I think you need to forget anything related to QOS your just wasting your time. VPN's use the public internet or local LAN but virtual private networks normally use L2TP (layer two tunneling protocol), L2TP creates a secure pipe across the internet or LAN & is encrypted end to end & requires as much available bandwidth as you can give it. QOS would take up a good chunk of that bandwidth and probably result in a VPN failing to work due to a lack of bandwidth. This is my understanding of how this works.
**Same applies to PPTP (point to point tunneling protocol).
**VPN yes! but NOT with QOS.
Ivan