Is Aldi really a good deal?

I've been hearing a lot about Aldi recently, and how they offer some really great deals on groceries. But is Aldi really a good deal? On one hand, their prices are certainly lower than some of the bigger supermarkets, but do they skimp on quality to make up for it? Are their products fresh and healthy, or are they just cheap and potentially harmful? I'm curious to know if the savings are worth it, or if I'm just compromising on quality for the sake of saving a few bucks. I'd love to hear from someone who's actually shopped at Aldi before and can give me their honest opinion on whether or not it's truly a good deal.