Will unlocking an iPhone 4S change its performance?

Will unlocking a phone like jail breaking it? Because I pad a jail broken iPod and eventually it ran really slow, I don't want that happening with this phone.

Hi, unlocking an iPhone 4S does not change its performance. Its just remove the network restriction and allow you to access any GSM network SIM card.
Jailbreaking will not unlock your phone. Its just remove the restriction and make the phone to accept third party applications, software.

To unlock your iPhone 4S visit the site http://www.classicunlocking.com/apple-iphone-4s/rs16wp9/ here they are providing the Remote Unlocking Service at low cost with easy step by step unlocking instructions and unlock it. After unlocking it, you can use freely any GSM network SIM card. This is the easy, safe, fast and permanent unlocking service. This method does not requires any Jailbreaking.

No unlocking is different from jailbreaking.

iPhone Factory Unlock is a permanent solution to free your iPhone from any SIM card restrictions imposed by Apple and your service provider, so that you can use it with any GSM SIM card provider worldwide (example T-Mobile).

It does not affect the phones performance.