Arrowhead is native to North America which helps its reputation here, but the folks in Australia and Europe consider it to be invasive (it's not native to their countries). It's like anything opinion related, if you are trying to get pickerel weed to grow and the arrowhead chokes it out , then you despise the arrowhead. In my case, the pickerel weed that I bought and planted didn't take and I am grateful for the arrowhead. I even have left a couple cattails (I think) in the pond for diversity. Don't hate on me yet, they have not gotten out of control by no means and will be easy to eradicate where they are located.
Overall, Arrowhead has got a good following. Be Aware that there is a similar plant called Arrow Arum that looks very similar, but is poisonous. There are also several Arrowhead house plants that look similar, but are not native and should not be planted in the wild.
Ducks like the seeds, but it is debated whether they eat the tubers or not. Water mammals, like beaver, will eat the whole plant.
The only downside for me is that after they bloom and fade, the stalk is rather ugly without flowers and I get temped to trim the stalk back, but I have been too lazy/busy for that.
