I use two DC, my primary already mention, is the Mares Puck Pro, it is a great DC and is very affordable price wise, the down part is that it does not come with the PC USB cable included, my secondary is a Suunto D4I, hate/love somethings about it, but it is probably the smallest DC there is, I used as my daily watch as well, they come with the PC USB cable included have the option for a transmitter, but they are not cheap, and I don't like the Suunto Dive log software I preffer the Mares Dive log software, the Suunto was a gift and that is why I have it, and I wanted a backup DC so the gift was spot on.
---------- Post added June 22nd, 2015 at 02:43 PM ----------
Petrel is hands down the best DC, but IMHO, it is more for tec diving, way overkill for recreational diving and staying inside the NDL, but it is not small, so it doesn't fit that description of what you are looking for, if you want to brag about having a Petrel and lookinga little dumb if you are using it for recreational diving only you can choose one, definately it is the best out there.