You may want to look at inbuilding radio surveys test devices such as Sagem or Anritsu. Drive test devices are all well and good and come with GPS. Problem is inbuilding can have little or no GPS signal at all. Also if carrying TEMS on backpack can be difficult sometimes inbuilding… Handhelds like Sagem can be helpful.
Also don’t forget Nokia netmon. Most moble telephones are not compliant calibrated once left factory and in the marketplace. Therefore calibrated devices give better perfromance than non-calibrated and used customer handsets may not get the same test results you do with calibrated devices. Just a suggestion.