Real Maraschino cherries - not the nuclear red colored things most people end up with in their Manhattans - are actually pretty rare. The candid red things most of us slipped from our parents cocktail cabinets are really imitation and artificial. I haven't been actively searching for the real thing, but ever since I did some research on the ideal Manhattan cocktail, I think they have been in the back of my mind.
Recently while walking around an older school, St. Petersburg, FL equivalent of Eataly, called Mazzaro's Italian Market, I stumbled upon the real thing: Luxardo's Original Maraschino cherries. I shied away from buying them for fear of ultimately ending up with cherry juice all over my luggage, but my interest has been renewed. I see that they are available on Amazon.com, but they seem to be more expensive than at Mazzaro's (and they were that cheap).
But honestly, with cocktails, any little thing can screw one up, from bad ice, to poor quality ingredients. So why skimp on the garnish?