I imaged an iPhone that was accidentally restored using an older backup file. The text messages for a certain date range were not visible from the phones GUI. When I imaged it using IXam, I was able to carve out most of the "lost" messages. The iPhone has an ability to store huge amounts of data and when that data is deleted out of the SQLite DB's it is stored in the UC and stays there for quite some time. I can't speak to other physical phone dumps because my experience is focused on iPhones, but it really works well in those cases where you are trying to find those few missing text messages that happen to be the "smoking gun". The process is little clumsy and requires some getting used to but if it's a gun fight, this tool is definitely the gun you want to bring. My .02cents.
My toolbox is forever growing with apps and utilities.
I have recently been using a new tool Craig Wilson's 'Blade' from Digital Detective, a good tool that one, and yet still find I use an old tried and trust pal called BCONV.