Okay. Right now I own a Whistler XTR-140. Surprisingly, it is a good RD for only $50. My friend owns a 6-Band Cobra RD. So last week, he hopped in my car and he saw my Whistler. He was like what the hell is that? I said it is a Whistler RD. I heard about it online. He never heard of it. When i drove around with it but i received some K-band false alerts. He said his Cobra RD is way better than my Whistler? I was like no Cobra is the worst RD ever! Even people from online said too. He was like whatever. So, which RD is better? Whistler XTR-140 or Cobra 6-Band?