Most of us use the gates kit. You will find problems with any thing if you look hard enough.
I used a Gates kit on my new short block.
The first time I used a Dayco belt and pulleys I got from Advance Auto Parts. It's all good.
174,000+ miles, 5/20/12 new ej257 short block, 8/20/11 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. Also CHECK YOUR OIL, these cars use it.