Whoa Scooby-wrx do you even drive your car? thats one tidy underside!
I run them arms in my RA had them in my gf8 as well they are about 15-20mm longer than factory the inner cv makes up for the added length... They are great good quality i've had a few secondhand sets of these in my hands and none have had any pay in the joints.
Only bad side is the swaybar link box thingy is very weak, i add large washes with standard swaybar because they bend.. if you upgrade your sway bar then you will have to look to welding steel plates in it to strengthen it up, Also you have to use a 14mm nut because you can't fit a 17mm spanner in there.
All the bother a side though they are worth it and do make a very noticeable difference
Edit... No Cert needed only adjustable arms.
They are more than just bling factor they are very high quality kit built to last:0