Yeah, it's a bad idea. The exhaust will damage lungs, trigger asthma attacks, and is carcinogenic as well. Loud exhausts are also extremely obnoxious and really just a cry for negative attention. On top of that a stock RB26 has pretty poor boost control so you will probably cause boost overshoot with a straight pipe which can damage the turbos from overspeed.
Terrible. I'm putting an HKS Hi Power with mid-resonator back on. Mine only has a small dustbin at the back, no cats, no mid section - basically a straight pipe. Sounds ok but drone just ruins the tone for me and it stinks to high heaven.