Liquid Coffee Concentrate...anyone use it?

I’ve heard amazing things about liquid coffee concentrate for years.  People tell me it’s the best cup of coffee they’ve ever had, and I hear this over and over again.  I grind my own beans every morning, but if concentrate tastes as good as I’ve heard, I may just give up the grind, so to speak.  If any of you’ve tried it, what’s your opinion?  I’d like to find a mild to medium roast, unflavored (and no chicory).  I’m not sure I have the patience to cold-brew my own (as with the Coffee Toddy), but I’d love to find something available in stores.  Mail order is such an expensive hassle, especially for grocery items.