I personally like the HD air shocks on my UC. I like being able to add air to customize the ride depending on 2-up or solo. I did go with the lowered version (54631-02B) since I have lowered the bike front and rear. THAT and the REACH seat has made a big difference to the perceived stability of the bike. This may not be as big an issue on the EG.
I spoke with the fournales man today by email.
He answered my questions on 3 emails + gave me some advice and technical recommandations + made me a kind commercial offer.
It's ok i'll go with fournales classic 13,5" + the air pump.
Thanks for your answers.