I like to keep as much of the extra weight on the bike as low as I can and this is the best (and only) place for heavy tools in terms C of G which is why I went for this. Mounting a tool tube or anything else is going to be a lot higher on the bike. Let's face it, your tools Kg/litre are going to be the heaviest/most dense thing you ever have to pack on your bike. However, everything is always a compromise - no solution is ever perfect!