I've travelled across Canada and tried seafood in just about every place that offers it (especially if it's a fishing area), and not one restaurant or chip truck, can stand up to Herbert's Fish & Chips.
You wont find that horrible greasy, thick, beer battered style of fish... what you do get is fresh fish caught from the great lakes, lightly dredged in a seasoned flour coating and then deep fried.
It's an hour's drive off the main hwy into Killarney but well worth it, not only for the fish and chips but at least for the chance to see a moose or two, black bear and deer while driving there and back!
We've been to Herberts many time's over the years, and always try to include it on our journey.