So we have a $300+ version and a $20 version. Please tell my why I should buy the K-Mac versus the cheaper option. I know they are totally different products, but will the cheaper version be effective and more importantly... safe?

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2002 X5 4.6is - Titanium Silver / Black Alcantara - Dinan Stage 2 - Bilstein/Eibach - Brembo BBK ----SOLD---
1993 318i - Brilliantrot / Tan - bone stock daily driver