There are certainly some good values to be found in the big box stores, but on the whole they cater to customers whose primary selection criterion is price rather than quality. That's a polite way of saying that some stuff is good, but they sell a fair bit of cheap, short-lived junk.

OTOH a high price doesn't guarantee commensurate quality.

Rule of thumb: you don't always get what you pay for, but you very seldom get what you don't pay for. Caveat emptor.

I've only seen a few Seagull lighting pendant and chandelier fixtures, but I was underwhelmed by the quality. For non-decorative under-counter lights I would go with one of the name brands sold by Home Depot.

In a re-model of the kitchen and bathrooms we bought all of the non-decorative lighting from Home Depot. That included recessed spots, under counter lights and waterproof shower spots. It works flawlessly.