I have always used a red Mastercraft Toolbox. It is affordable, it does not give away what's inside, it's lockable, it's metal (durable), and I can easily fit three full-size 1911s under the tray which holds all of my mags and various range accesories. I even keep all of my 'paperwork' in there. The other hand can carry the ammo.
I keep each gun wrapped in a large enough towel to keep them free from hits and dings, and to secure them in the box so they don't move around (they stand up side by side). Also, the towel, in addition to the box itself, helps keep the guns from getting potentially frosty if moved indoors from cold outdoors.
It may not be the most glamorous, but it works really well. Besides, for transport, I'll trade glamor for concealment, all things being equal, any day.
