Well I guess I am one of the "old few" that support them. I have one. Had it for many years. YES it does work. (It won't necessarily catch the fish for you!) But it does make the fish more active and easier to catch. I have had service work done on my old model with good support from the company. I have had good support from the NEW folks. If you have any problems then contact John Braig. (He is on this forum.)
As for specific results: I have had boats follow me around and wonder why they were catching fish when they were close to me. I just laughed when they talked to me as they passed by.
I have seen NUMEROUS times the bait fish school up along my boat and even follow the trolling motor in schools. I have had fish school up all around my boat and had bass feed on them with the hydrowave on. And turn it off and it all the activity then dies down. I have changed the settings and started to catch fish and change back and fish not bite.
NOW the question for you is this: Is it worth the investment for your type of fishing??? Personally I do not consider a PowerPole/Talon worth MY investment because I spend most of my time fishing deeper than they will reach. Is a Side Scan Humminbird/Lowrance worth MY investment then that answer is YES (FOR ME)for my style of fishing.
I fish tournaments, so every edge I can get helps me in a tournament. I don't expect it to be a "silver bullet"! If the fish are biting more favorable on one style bait and I throw a jigging spoon in the grass then realistically it is not going to benefit! I love when other anglers do not use one or have one. One less thing I have to be concerned about!
p.s. I am not a Pro and NO I am not getting paid to promote or support their product.