You extend the shelf life by adding sulfites. One crushed up Campden tab per gal will protect the wine. I'm assuming you mean grocery concentrate for juice not concentrate specifically for wine making. The reason some say that concentrate wines don't age well is because they typically don't improve much over time as most wines do.
Primary: Sparkling White Grape Peach Wine
Secondary: Coco-Strawberry Wine, Pumpkin Wine, Apple Cider
Bottled/Aging: Pear Wine, Strawberry Wine, Blueberry/Blackberry Wine, Mixed Berry Wine (Blueberry, Blackberry, Strawberry, Raspberry, & Cherry), Jalapeno Liquor, Skeeder Pee