Which is the correct way to configure my tunnel. Both ways work but which is proper.

Data Vlan= 192.168.10.0/24
Voice Vlan=192.168.55.0

I was taught to create a loopback address such as 172.16.16.1/24 and send the tunnel to that address. Then I enable split tunneling to protected networks 192.168.10.0 and 192.168.55.0 with wild card mask of 0.0.0.255 and let the router route to its proper destination. I recenty changed my VPN config to just point to the Data vlan and enable the split tunnel. Is it just pointless to make a loopback or is that a good security practice.

*Note* My IP communicator works fine on either setup.