OK, so the choice are

Fulltraction 5100 series hydraulic shock
Bilstein 5100 Gas Charged shock

right?

Since my JK is mainly on highway, please let me know which one is more suitable for
comfortable (soft) high speed travel?

Also, if I want to use Old Man Emu shock, besides the requirement 27 inch in length,
any other things needed for this kit? such as longer bump stop?

There are multiple choices of Old Man Emu shocks, will the long travel version work for it?

 

talk to Dave at Northridge about the OME.

You are correct, the only choices from us are the Fulltraction 5100's and the Bilstein 5100's

 

Just ordered the Fulltraction premium 3 inch kit from NorthRidge4x4

I read wayoflife's writeup on ultimate 3 inch kit. It is quite straightforward
and I am quite confiident this job can be done within 2 days with a friend's
help.

Here is my major concern. WayofLife's write up is dealing with ultimate kit,
so it provides the length for both upper and lower control arm.
But my kit only comes with upper control arm, so I guess the length it needs
to be set is different. But can anyone tell me what it should be?

Thanks!