That kit bag is nice. It has all kinds of internal dividers that you can move around to set it up to meet your needs. It will hold the camera with 1 lens mounted, both of the other lenses, and still have a pretty big compartment open for accessories or another 2 lenses. Plus, it has a zippered pouch on the inside top, and two more on either side of the bag.
Yes, I did buy from Amazon, but don't tell Supe. He might not be happy when he finds out that we paid less for both the kit and the 55-250 than he did for just the kit. In fact, I probably got that 50mm lens thrown in for less than what he paid too.
The prices were significantly higher everywhere when I looked, Amazon included. Looks like I bought everything just before the holiday price drops came. No big deal though, I did get the tripod thrown in and also have a ginormous memory card. I don't regret the purchase at the price I paid since it's come in very handy both at work and on my road trips.
As for the case, it definitely fits everything you need it to, but if you carry it slung over your shoulder, the plastic clips for the strap will begin to squeak and drive you insane.