You can have a pistol grip in california, but that means that your mag release will require a "tool" to operate. In otherwords, you are not allowed to have a pistol grip and a detachable magazine, but a bullet button is an option.
The grip that is on there circumvents the requirement of a fixed mag, since your thumb cannot wrap around the grip, so you are allowed a detachable 10 round magazine.
Either way, it is essentially neutering a great weapons platform.
Oh, and +1 on the Forward assist NOT being a band-aid. It is a great tool for when you are chambering a round and you need to be stealthy about it. Its a lot quieter to follow the bolt forward and then just press the FA until you are in full battery. Much quieter than a loud "CLANG!!!"