"I heard performance is better on openvpn?"
Where did you hear that? Openvpn does most of its things in user mode. IPSecure does most of its things in Kernel mode. Which means, IPSecure can give you double the speed as compared with Openvpn using the same cipher. There is a quick speed comparison on www.punchvpn.com/FAQ.html
"are both ipsec and openvpn equally secure?"
They both use the same underlying encryption algorithms like Blowfish, AES, 3Des etc. By default, openvpn will use Blowfish which is super fast on non accelerated CPUs. However AES would perform better on CPU's which support special instruction sets for AES. However majority of routers (like 99%) do not use those CPUs which would favour AES. In my opinion both Blowfish and AES are secure. So security wise, I don't see any one having edge on the other because underlying encryption is the same. Openvpn does enforce server side certificates and has no mode which can do without server Certifiacte. IPSecure can do either. i.e Certs or no Certs. I personally like flexibility and dont like to be forced to use one method. I also like speed, which openvpn lacks when it comes to routers. In addition, IPSecure is more of a standard thing and is available by default on almost all platforms, where as Openvpn requires third party software installation on almost every platform. In summary, I would prefer IPSecure over openvpn. But thats just me. Software wise, openvpn is a good piece of software, I have nothing against it, except the stuff that I mentioned.
"can i set up ipsec in luci?"
I never use luci, so I wouldn't know.