No your engine light will not come on (engine does not equal suspension). If your not going to get stock you have a few options Blisten and Tockico would be the best (IMHO). Koni is ok too but I would stay away from KYB and sachs-boge these two are really soft and not IMO any good.
I don't live in Cali so I have no idea where a good place is to get such stuff done but you can do it yourself. There is a special tool required to set the torque on the cap of the strut assembly make sure you have this tool (I didn't have it and I had to wait a month to get one shipped to me, and nissan didn't have the tool either). Good luck with the car.

 

To my knowledge , the only thing that will happen if you don't use the OEM struts is the small lights on the S/N/F adjustment dial will light up all at once , and may possibly blink.

 

Try Z Whizz on Aero Drive just off the 15. I havent personally had work done there but know people who have, and have stopped by and chatted with them a few times. They seem very knowlegeable and love their z cars. They are a bit pricey, but so is any other mechanic!