Viltrox?

Hi All,
Just bought a pansonic G80/5 after using canon 40D for many years. Got the kit lens with the 80 but have a mixture of lenses from canon,sigma and tamron for the 40D. I still intend to use the 40D but would like to expand lens range for 80. Would it be best to get viltrox for 80 or to buy native lenses?
Just bought a pansonic G80/5 after using canon 40D for many years. Got the kit lens with the 80 but have a mixture of lenses from canon,sigma and tamron for the 40D. I still intend to use the 40D but would like to expand lens range for 80. Would it be best to get viltrox for 80 or to buy native lenses?

Some reviews comments on the Viltrox Speedbooster can be found here:
https://www.dpreview.com/forums/thread/4344310
https://www.dpreview.com/forums/thread/4344310