Why would anyone buy a performance kit from JCW?

[GTS 2.4]

I must be missing something here but when i went on the JCW website the top of the line performance pack for the 2007+ mini cooper S they had was about 2k and only showed gains of 8 hp and 8tq. they also had a kit for the 2006- models and it was 4.3k for 20 hp. Is this kind of pricing typical of performance parts for minis or is JCW trying to gouge us all on prices? The only thing I could think would make someone even begin to consider JCW is that I think your warranty is unaffected. maybe Im wrong but Id appreciate any info/insights you might have.

[bad venge]

The JCW is pricey but there are other things Upgraded brakes/struts/springs and rim tire combos.
There are cheaper ways to get equal performance without the price and yes it can affect the warranty