This thread is going to take a turn very quickly... sorry OP, but you got the answer you need, so the rest of this is just filler.

Cool story. But, you aren't your buddy. You aren't a source that should be trusted for any reasonable piece of advice other than for the next owner of the cars you have touched, so they know what is broken.
Also, you don't know what you're talking about, especially when it's related to this conversation -- specifically the use case in which the OP is looking for the best brakes for his street setup.

Is that your basis of "I know what I'm doing"? Adorable.

My R53, with mods, was purchased for $1400. You spent that on hilarious junk like tow-hooks for your hardparking, and fake carbon fiber junk.
I have two other cars, that I'm 100% certain that you and your Mini would never catch on a road course, unless I stop and grill up a steak, clean the interior, and swap the brakes. Only then would you finally catch up when I get the last wheel bolted up.


I have, comical. The ebay wing is a nice touch. project "rice" indeed.

 

.....I have something much faster than a MINI in my garage....if straight line acceleration is the goal

 

Don't miss that we were talking about R56 JUSTA brakes (280 mm), not R56 MCS brakes (294 mm). R56 JUSTA brakes easily fit under 15" wheels. R56 Justas used to come with 15" wheels from factory. Rephrasing doesn't change much on that. R56 Justa and S = same calipers, but different brackets, different size rotors and slightly different pads. There's a reason the brackets say 'TRW15' and 'TRW16'.

 

Really useful and practical post- I knew about the brackets from all the reading on this topic, but I still had not understood that the rotors were different sized. This 3 sentence post is basically the whole swap in a nutshell! Thanks!

 

Brakes are like any other performance part. Each part has its own level of durability be it billet or carbon fibre. The key is finding balance based on the materials and also dimensions. Everything needs to be considered, driving style , load and frequency of use be it high or low. There is no point in getting a big brake kit if you gonna be doing 60km/h 90% of the time, your brakes need a certain level of good operating temperatures based off driving style. If you driving quick all the time from light to light , on narrow winding roads , yes you will benefit from slotted and drilled rotors (which helps keep temps in ideal range for that style of driving) if it's track racing , slotted,drilled and thickness aswell materials will all come into play to keep the rotors in ideal operating conditions. A great brake system is one that is balanced for your style of driving and what you are using the car for. To keep carbon ceramics in ideal temps on the road is a lot harder than when it's on the track but steel rotors is a lot easier to keep temps in check on the road but if you always using the brakes and feeling it's fading after heavy use... Even though you swapped out brake pads you still getting brake fade that's when you should consider vented rotors with little bit of drilled and slotted patterns.

Start with brake pads, brake lines, brake fluid then once you did all this and you still getting brake fade , then move to vented rotors etc and if that Fales then you will need a big brake kit etc until you get your perfect brake pedal feel based off your style of driving.