In my experience that depends on what is the v4 path between you and HE's PoP and how good is you v4 ISP in regards to peering agreements. In most places where

In my experience that depends on what is the v4 path between you and HE's PoP and how good is you v4 ISP in regards to peering agreements. In most places where I used HE tunnels the latency through the tunnel was actually better for vast majority of sites I care about (which is simply effect of HE having global network and huge amount of peering partners).