Please help me understand bumper steer, camber, toe kits, and extended ball joints.
 

Hi forum,

I'm having trouble understanding the few items mentioned in the title, use megan racing as a example, they have front bump steer kit (little long-looking spacers), front roll center adjusters (offset ball joints with spacer), rear toe arms (toe arms with what looks like ball joints with spacers), and a rear extended ball joint pair (just extended ball joints, looks a lot like spoon's rear zero bump steer kit).

My question is: Are all these items meant to work together? I sent megan racing an email, they replied with something rather confusing. I thought maybe forum will give me a more direct answer, basically I'm trying to figure out is whether fixing the roll center will reduce bump steer, I know they are different things but it seems like the method of fixing both is to space out the ball joint.
So question 1 is whether spacing the ball joint fixes both roll center and bump steer, that's certainly what spoon's kit is trying to do.
Question 2, the most confusing thing from Megan's reply was that they said they've never advertised their toe arms as a bump steer kit, but from everywhere I've searched they are indeed a bump steer kit, right?
Question 3, Megan replied that the front bump steer kit (the flat spacers) is the option to go with if I wanted to keep the stock ball joint, so the flat spacer and the roll center adjuster do the same thing? Then why would anyone buy the more expensive ball joints while the bump steer spacers are much cheaper? What if I use both on the front suspension?

Much Thanks if any of these get answered
Wei