Intrathecal AAV9 works excellently to get DRG neurons in the lumbar region. I injected the same AAV-hSyn-EGFP (10^13), 10 ul, and got very high expression. In light of the recent work looking at promoters in DRGs, I bet CAG would have been even better.
However, it also hits spinal neurons and probably higher CNS areas (as reported)
Spinal cord