Here is what I am doing and it works for me. I use two bags.
I have a Lowpro Nova 3 which will fit the 2100, b-300, b-28, a bunch of filters, mini tripod, cables, cards, batteries. . .etc. I use this when traveling to keep all my stuff together.
I also use a Tamrac 515 which holds the camera and has a bigger pocket than the 5516. The 515 will hold the camera, three sets of batteries, cards and one or two filters in cases. I then bought two large lens cases designed to attach to the side of the case which I use when carrying the b-300 and/or b-28. They also provide space to carry filters and other stuff as needed. When I don't carry extra stuff, they detach. By the way, I put an old pad from an old carera case in the nose of the case for extra protection should there be a "nose drop".
I had a TLZ Mini and felt that it was too snug. I worried that the display would get scratched. The 515 gives about 1-1 1/2 inches of room so when I added an upgraded strap, the strap fit in. I don't think that it would have fit into the TLZ Mini.
Cases are personal to everyone. Take your camera to the store or a few stores and try it out and see what pleases you, not everyone else.
Mike
