Site2Site is traditionally IPSecs business. You could try tinc, it's really cool.
For end users, I tend to use OpenVPN because it's no hassle to install at all. But there are other cool solutions on the rise, waiting to be audited and to be proven. I particularly like the concept of SigmaVPN, utilising djbs NaCl for secure encryption at blazing fast speeds.
In the case of OpenBSD, I also tried to deploy IPSec for end users and it did work well, too. (However, IPSec on OpenBSD is foolproof to install. I did not fiddle things out on pfsense) If you look out for papers, IPSec is superior to all other VPNs in terms of speed, jitter and performance on bad network conditions. It has very little overhead, too. That comes in handy if you're working on the go using 3G and you used all your high speed data on your mobile plan - while OpenVPN tends to fuck the whole situation up (No productive work possible on RDP, ssh seriously delayed in comparison to IPSec), IPSec performs pretty well.
I'm however continuing testing. Hope I could help.