I carried one like Mahlere for several years until my tools wore thru the material and scratched a customers floor.
Now I carry a Veto Pro Pak
http://www.toolsandaccessories.com/a-B00009K77K/Default.aspx It's heavy but holds everything. Works good for resi service calls. Carries what you'll need for a quick trip from the truck to the customers door and reduces the number of trips back to the truck. It's not something you'll carry very far. I think it weighs 12 lbs empty.
Mostly, I carry a 10 in 1 Klien screwdriver, side cutters, and needle nose in my pockets.
[This message has been edited by PE&Master (edited 10-16-2006).]