Has anyone used QGIS as an alternative to Terrasync or ArcGIS mobile?

We are planning to purchase a rugged field computer (Trimble, Juniper, Ashtec etc.) for accurately surveying habitats and work sites in remote locations. In the past we have found that the software from ESRI or Trimble will cost nearly as much as the machine. We have occasionally used QGIS in the office on PCs that don't have a licence for our MapInfo GIS (with reasonable results), so I am wondering if anyone has tried using QGIS on any of these professional mobile mapping devices? I can see from online comments that there have been numerous issues with attempts to use QGIS use on tablets, mobiles etc so I am keen to know if there is a device that I can be confident it will work on.

Thanks Simon