Congradulations on the 530 man!!
I just picked up my 530 a few weeks ago. I've only got a few hundred miles on the bike yet, but I'm having an absolute blast on it.
I went with the 14/50 gear combo and it's great. I haven't found myself hunting for a higher gear at faster speeds with that setup.
I replaced my seat with the EE seat and for the price it's great (130 with the pan). I'll send off my stocker to Renzaco to get my long term seat made before too long. (Can't decide to do the seat first, or the steering dampner).
What I found amazing was that after the bikes canister removed, and unplugged just how much raw power it has. It's just downright scary!