The groceries are priced near those offered by Giant Eagle (if not a little more). The quality of groceries and meats is also in the region of the general Giant Eagles (with the Market District Giant Eagle having a significantly larger selection).
I wouldn't consider the basics to be a bargain by any margin. Sans sales, the prices I've seen at Target (in East Liberty) are generally lower than ShurSave. I'd also recommend Groceria Italiana a few blocks down for quality deli meats at low prices.
I think the best bargains here are the items that are on promotion. I was able to find items such as body wash at prices below what I usually pay while it was on promotion. Unfortunately, it's a hassle for me to stop by ShurSave just for promotions. If you live nearby, then ShurSave is a great resource as a convenience store when you're in a pinch.