I wanted a bag similar in size to the Slingshot 200 but able to carry a 10.1 inch laptop. I also have a Compu Rover, but all the camera gear is in the bottom and I prefer sling-type bags. Also, the bag is too bulky for some situations. I saw the Kata 3n1 bags online but there were none in stock locally. I came across the Tamarac 5788. It fit my needs pretty well. It can hold the following gear:
Main Bag Area
1000xS with 100-400 attached, including mounting ring
Depending whether you put the lenses vertical or horizontal, there is enough room for at least one more lens the same size as the 24-105, lens hoods for 10-24 and 24-105(detached) or mount the lens hood on the 100-400 reversed.
Assorted cables, including laptop power supply
I prefer to keep the Lens hoods for 100-400, 10-24 and 24-105 in this area. There is still room for the speedlight, some cables and the Rocket Blower
10.1 inch laptop
If you remove the items from the top area, there is enough room for a second camera the similar in size to the 1000XS with the 24-105 attached (lens hood reversed).
My one issue is that the bag does not “sling” as well as the Slingshot, due to rubber material on the shoulder straps to prevent slippage. While I appreciated this while traveling through airports, the sling motion was not as smooth as the Slingshot. Overall I am impressed with this bag and would not hesitate to recommend it to others.