I just want to confirm that you were able to get this onto your '17 Si Coupe without any fitment issues? I heard that the Tanabe bars often heat up and burn some of the tubing since it doesnt clear all the stuff under the hood.I decided on the Tanabe and ordered it from RCA- Race Consulting Agency for $112.59 with free shipping. It arrived quickly, great service. I did install it with the wheels off the ground an no load on them. I did have an issue using a socket to tighten 1 nut on each side with a ratchet and used an open end wrench. I am not sure if this would have been required had I just done it on the ground. The nut is extremely close to the mount where the bar bolts in place. After a drive I am not sure how much if a difference it makes because I did not push it to its limits before. I will say the front on the Si in Sport mode handles like its on rails.
http://raceconsultingagency.com/tanabe/tanabe-sustec-tower-bar/ttb197f/i-3739426.aspx