My parents both drive Jeeps - a '13 Grand Cherokee and a '13 Wrangler Unlimited, Sahara. They are both very nice cars (and can be quite a bit more expensive than the CX5). Speaking specifically about the Grand Cherokee, I think it has a more 'premium' feel than the CX5. Of course they are not direct competitors (but are sometimes cross-shopped), the space, ride and fit/finish in the Grand Cherokee is unsurprisingly much better. It is a nice car and has moved up-market in recent years. I live in Houston, and I see at least a dozen of them everyday.
When I bought my CX5, I was considering a Grand Cherokee, but I am very happy with the CX5. At the end of the day, I had to look at price vs features/benefits and I think the CX5 is a tremendous value. While smaller, I think the driving dynamics are much better - it feels more connected to the road. The smaller size of the CX5 is better for me because I live in the city - really tight parking spots and garages at both home and work. For my needs, it has enough space for people and luggage/other items but perhaps that might not be the case for everyone. And as speed pointed out, the gas mileage is much better in the 5 - I am averaging in the neighborhood of 25.5 right now with 85% city and 15% highway.
At the end of the day, you can't go wrong with either!