It is still quite expensive, the kernel module is still faster. Performance depends a lot on your kernel version and network card. We measured anywhere from 20% to 40% advantage to kernel module. But we are working on additional performance features, such as using send/recvmmsg and raw sockets.
Thankyou, that is even better than what I would expect. I have been trying to tune around similar issues in tinc-vpn which also runs in user space and depends on newer kernels and code changes to work around.
