The mustad knife is cheap and keeps an edge:
https://amzn.to/30n72FG
I used the Tsunami 6" but they discontinued that. Rapala also has some nice looking knives on Amazon, but I've never used them (yet). Just get a good sharpening rod or whetsone and don't put your knives in the dishwasher and you'll be good, even with a Wal-Mart knife