Injen CAI or Gruppe M?

[im_visvim]

Not quite sure the difference between these 2
All I know is Gruppe M is a lot more expensive than Injen CAI
How about the performance? as well as the sound when hitting the VTEC?

[infurNOS]

wasnt hard to search

http://www.ozhonda.com/forum/showthread.php?139076-gruppe-m-vs-injen-cai-sound&