If buying only one pair of dressier cords - Wale? Color?

I am going to purchase one single pair of nicer, more dressy cords today (thanks Lands End for the 30% off sale). If you wear going to do the same, what Wale would you select, 10 or 18? Also, what color would you chose to cover lots of bases?

Thanks

If buying only one pair of dressier cords - Wale? Color?