Topeak's Hexus is a good size, has everything you'll need, including a chain tool and tyre levers, but we were left feeling slightly underwhelmed. The tolerances on the Allen keys and the torx weren't good, and there was a significant wobble factor.
Our more brutal tester (and there is always one who can only use tools in full-on destructor mode) wasn't confident they'd last long in his hands before rounding off. There's also something fussy about the way all the tools are ordered, and it's not the easiest to work with when you've got cold hands. That said, the chain tool was simple to use, and the snap-off plastic tyre levers were quick and effective.