brake rotor quality

[Gurjit]

im on the verge of buying new brakes, front and back
I just installed ecs drilled and slotted rotors with akeenbo ceramics in my brothers 2005 530i
-after bedding them in they perform well. initial bite has decreased slightly but not a big difference. warmed up the brakes are wonderful.
-also installed the S.S. braided lines

ecs also has a kit for my 4.8is for 666$ drilled+slotted or only slotted
-but the price of these rotors scare me
-unlike my brother who drives normally, I drive my suv like a stole it
-multiple +190km/hr brake applications really took a toll on my oem pads

-I believe in the ecs redstuff pads for low dust and higher performance from all the forums and stuff I have read.

-but the low cost of the ecs rotors has me scared. we have all heard of that saying you get what you pay for.
-just cautious of my own safety, as oem's gatta be designed for the beast +250km/hr otherwise bmw wouldn't make the tank move so fast

-I will not buy drilled and slotted for the x5 because of all the cracked rotor hype around drilled brakes

-the oem rotors have not let me down, no vibration, no warpage after 1.5 years of hard driving they lasted me +50,000km
-the pads let me down a couple times, faded on me before and the dust is ridiculous.

front pair= oem blank 333$, brembo blank 230$, ecs slotted/drilled+slotted 195$
rear pair= oem blank 181$, brembo blank 193$, ecs slotted/drilled+slotted 135$

what rotors do you guys have experience with on your x5s?
anyone have tech info on run-outs, metallurgy?

what is the oem brake rotor minimum thickness? the rotors where brand new when I bought the suv off last owner, I wounder if they are designed to wear with the pad or last a pad change