Don't root you're phone just for a fps fix. It's pretty stupid to void your warranty just for a fps fix. But that's just me
I actually think it's stupid if you choose not to root because of warranty.
The FPS fix makes things so much better that I can NEVER go back to 30fps... I would rather keep this Cyanogen RC1 instead of having fully functioning Sense 2.2
I actually rooted my phone JUST for the fps fix... makes my phone super smooth in scrolling/normal usage and games run so much better.
You can always unroot to send a phone back for a warranty replacement.