I was in your shoes 2.5 years ago. I was into the Genesis line, but couldn't decide what. I really wanted the sear burner, but not the side burner. I ended up going for the 330, and it's really been a fabulous grill.
I don't use the sear burner as much as I thought I would. If anything, like Grimm, I just use it as a fourth burner to heat it up faster or something.
I tried to use the side burner once to boil a pot of water for corn. It took FOREVER to boil. And now we have an induction range inside, so I wouldn't mess with that anyway . . .