Hermès, because everyone recognizes it. E. Marinella for summer ties. Drake's for the cooler climate and british style. Kiton. Well, because it's Kiton.
Honorable mentions
Fumagalli 1891 - the oldest Tie-maker in Italy, RL Purple Label - the High Fashion section at Ralph Lauren, Brioni - if you want Kiton but can't afford it, Ferragamo - the Italian pendant to Hermès, Brooks Brothers for a diverse selection of decent quality on a budget.