Some good points already. I have WSPS fitted to the Bell 407 I get around in and I must say, it is a nice bit of kit but it doesn't or shouldn't stop you from looking out for wires. If you miss the gap they still get you..........
But then I suppose you don't really hit the ones you know about or see, it's the ones you DON"T see.
I haven't had to pay for the system but it does leave you with something of a warm glowy when you are making approaches to properties out in the sticks where wires can be anywhere that Farmer Ed feels like stringing them. It does assist with your wellbeing a little bit.