Tein RS are perfectly usable for the street. They are 559lb in front and 559lb rear.
They are almost the same exact coilover as the Tein RA. Main difference will be the RS comes with the external oil reservoir. Which are more suited and designed for the track use. But you can use these coilovers fine on the street.

The Tein N1 spec is the one Tein will email you not to use on the street. I have talked to them about this coilover before. Which will be releasing for the s2000 soon. They are for full track use.

 

The EDFC is compatible with Flex. Not with CS, RA, RS.

 

I think im going to get the Tein CS due to the price i can get it for. I would want the Zeals since it seems better (name brand wise), but it costs about double. I dont quite think its worth the money so im in the process of ordering the Tein CS's.

After i get them, i would want to install these myself. How hard would it be?

 

i'm running the buddy clubs on the softest setting and its still pretty hardcore for the streets...they are more for the tracking events than daily driving...i am switching to a less hardcore coilover system for the streets later in the the future