I think they are worth it. I'm going to stay N/A for a while so every little mod helps. I'm about to finish my N/A build with stage one cams, LT headers and HPS hardballer intake (should be close to 300rwhp). So if you are going to be N/A for a while order some up.
+1
I have had mine for a long time now and have been happy with them. It wasn't a huge increase but it all adds up...I might have to take them off eventually if I go the supercharged route...