Padanky, I ran through the list of suspension differences a couple weeks ago, and came up with
Springs
Struts
bump stops
stabilizers
stabilizer bushings
rear stabilizer brackets
endlinks
rear crossmember
front crossmember
The whole bundle was around $1700 for Mazdaspeed members. I noticed that you did not list the front crossmember, which just happens to be $550 and accounts for how much less you paid for your parts.
So does anyone know what the differences are between the P5 front crossmember and the MPS front crossmember? I've read that the rear crossmember is reinforced to handle the stiffer rear swaybar, and shaped differently to allow room for the differently-shaped rear swaybar. What is the purpose of the different front crossmember?