Comparing the two fragrances…

Grès

Le Galion
Alix
Megara
Only in Alix
Shared character
Both Alix and Megara feature a combination of bergamot, sandalwood, musk, oakmoss, cedar, and aldehydes. They share several olfactory profiles, including floral, woody, chypre, green, powdery, earthy, and mossy accords.
How they differ
Alix incorporates spicy notes, amber, patchouli, galbanum, floral notes, and labdanum, resulting in citrus, aldehydic, leathery, amber, and warm spicy accords. Megara contains jasmine, gardenia, rose, cedarwood, orchid, peach, lily of the valley, raspberry, ambergris, hyacinth, iris, honey, and orris, which contribute to fruity, spicy, fresh, and white floral accords.
Who each suits
Alix suits those who prefer leathery, amber, and warm spicy profiles. Megara suits those who prefer fruity, fresh, and white floral profiles.