The high-gloss finish will reflect light into the eyes of the player and cause eye-strain. Best to use a finish with no-gloss for serious players.
Polar,
I own a couple of glossy sets, under normal lighting conditions there isn't an issue with glare. The problem arises with spotlighting. Pictures on vendor websites can be a bit misleading as the additional lighting required for the photoshoot intensifies the glare.
Staunton Castle has tried to produce a better copy than Chessbazaar but still has not been able to get it right specially as the bases of all the chessmen retain a normal staunton character. Noj reproduction is still the most accurate and best.
I would agree if you're referring to the original NOJ 1950 set. No question. But the latest NOJ version appears to have a few changes which for me detract from the appearance. There is a separate thread on here discussing this.